If 25% of your math class received an A, how many students were in your math class if 9students earned an A for the semester?

Answers

Answer 1

Answer:36

Step-by-step explanation:

Assume the total number of students to be x

According to the question

25% of x =9

⇒x=900/25=36


Related Questions

Let be two sets E and F such that:E = {x € R: -4 ≤ x ≤ 4}F = {x € R: | x | = x}What is the Cartesian product of the complement of E × F =?

Answers

Given:

[tex]\begin{gathered} E=\mleft\lbrace x\in\mathfrak{\Re }\colon-4\leq x\leq4\mright\rbrace \\ F=\mleft\lbrace x\in\mathfrak{\Re }\colon\lvert x\rvert=x\mright\rbrace \end{gathered}[/tex]

If |x|=x that mean here x is grater then zero.

E is move -4 to 4 and F is grater then zero that mean multiplication of the function is obtaine all real value:

[tex]E\times F=\mleft\lbrace x\in\mathfrak{\Re }\mright\rbrace[/tex]

Solye for x.7(x - 3) + 3(4 - x) = -8

Answers

[tex]x=\frac{1}{4}[/tex]

Explanation

Step 1

apply the distributive property to eliminate the parenthesis

[tex]\begin{gathered} 7(x-3)+3(4-x)=-8 \\ 7x-21+12-3x=-8 \end{gathered}[/tex]

Step 2

add similar terms

[tex]\begin{gathered} 7x-21+12-3x=-8 \\ 4x-9=-8 \end{gathered}[/tex]

Step 3

add 9 in both sides

[tex]\begin{gathered} 4x-9=-8 \\ 4x-9+9=-8+9 \\ 4x=1 \end{gathered}[/tex]

Step 4

divide each side by 4

[tex]\begin{gathered} 4x=1 \\ \frac{4x}{4}=\frac{1}{4} \\ x=\frac{1}{4} \end{gathered}[/tex]

a) Consider an arithmetic series 4+2+0+(-2)+.....i) What is the first term? And find the common difference d.ii) Find the sum of the first 10 terms S(10).b) Solve [tex] {2}^{x - 3} = 7[/tex]

Answers

Answer:

Explanation:

Here, we want to work with an arithmetic series

a) First term

The first term (a) of the arithmetic is the first number on the left

From the question, we can see that this is 4

Hence, 4 is the first term

To find the common difference, we have this as the difference between twwo subsequent terms, going from left to right

We have this as:

[tex]2-4\text{ = 0-2 = -2-0 = -2}[/tex]

The common difference d is -2

ii) We want to calculate the sum of the first 10 terms

The formula for this is:

[tex]S(n)\text{ = }\frac{n}{2}(2a\text{ + (n-1)d)}[/tex]

Where S(n) is the sum of n terms

n is the number of terms which is 10

a is the first term of the series which is 4

d is the common difference which is -2

Substituting these values, we have it that:

[tex]\begin{gathered} S(10)\text{ = }\frac{10}{2}(2(4)\text{ + (10-1)-2)} \\ \\ S(10)\text{ = 5(8+ (9)(-2))} \\ S(10)\text{ = 5(8-18)} \\ S(10)\text{ = 5(-10)} \\ S(10)\text{ = -50} \end{gathered}[/tex]

FIND THE INDICATED PROBABILITY A magazine did a survey to determine its readers favorite types of shoesFavorite types of shoes worn Sneaker boot Sandal other 54% 16% 20% 10% What is the probability that the sneakers Will NOT be the favorite shoe of the next reader?

Answers

In this case, we'll have to carry out several steps to find the solution.

Step 01:

data:

table:

favorite types of shoes

Step 02:

probability:

probability (not sneakers) = 100% - 54% = 46%

The answer is:

probability (not sneakers) = 46%

Simplify the expression (6^2)^46^?

Answers

The given expression is

[tex](6^2)^4[/tex]

We would apply the rule of indices or exponent which is expressed as

[tex]\begin{gathered} (a^b)^c=a^{bc} \\ \text{Therefore, the expression would be } \\ 6^{2\times4} \\ =6^8 \end{gathered}[/tex]

f(x)=1-x when f(x)=2

Answers

By solving the equation, we know that f(x) = 1 - x is - 1 when f(x) =  2.

What are equations?In mathematical equations, the equals sign is used to show that two expressions are equal.An equation is a mathematical statement that uses the word "equal to" in between two expressions of the same value.As an illustration, 3x + 5 equals 15.There are many different types of equations, including linear, quadratic, cubic, and others.The three primary types of linear equations are slope-intercept, standard, and point-slope equations.

So, f(x) = 1 - x when f(x)=  2:

Solve for f(x) as follows:

f(x) = 1 - xf(x) = 1 - 2f(x) = - 1

Therefore, by solving the equation, we know that f(x) = 1 - x is - 1 when f(x) =  2.

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Interpreting the whale population on the graph. I think (A).

Answers

The y-intercept is the value in the vertical axis (y-value) when the value on the horizontal axis is zero (x = 0).

Looking at the horizontal axis, the value of x indicates the generation since 2007.

That means x = 0 indicates the generation in year 2007.

The value of y for x = 0 is 240, so the population in year 2007 is 240.

Correct option: A

20) Determine if the number is rational (R) or irrational (I)

Answers

EXPLANATION:

Given;

Consider the number below;

[tex]97.33997[/tex]

Required;

We are required to determine if the number is rational or irrational.

Solution;

A number can be split into the whole and the decimal. The decimal part of it can be a recurring decimal or terminating decimal. A recurring decimal has its decimal digits continuing into infinity, whereas a terminating decimal has a specified number of decimal digits.

The decimal digits for this number can be expressed in fraction as;

[tex]Fraction=\frac{33997}{100000}[/tex]

In other words, the number can also be expressed as;

[tex]97\frac{33997}{100000}[/tex]

Therefore,

ANSWER: This is a RATIONAL number

Identify the coffecient of x in the expression below.-5x-4y^2

Answers

A coeffecient is a numerical or constant quantity placed before and multiplying the variable in an algebraic expression,

So in the given expression, the value "-5" is placed before x and hence is the coffecient of x .

Answer:

Step-by-step explanation:

3

The perimeter of a rectangular room is 80 feet. Let x be the width of the room (in feet) and let y be the length of the room (in feet). Write the equation that could model this situation.

Answers

Answer:

2x+2y=80

Step-by-step explanation:

a rectangles perimeter has the formula of width+width+length+length

we can combine like terms so we get 2x+2y and according to the problem this rectangle has the perimeter of 80

Nikolas bought a Falcon's ticket for $80. The sales tax on the ticket is 7%. How much was the tax?

Answers

ok

100% ---------------------------- $80

7% ---------------------------- x

x = (80 x 7)/100

x = 560/100

x = 5.6

The tax was of $5.6

A play court on the school playground is shaped like a square joined by a semicircle. The perimeteraround the entire play court is 182.8 ft., and 62.8 ft. of the total perimeter comes from the semicircle.aWhat is the radius of the semicircle? Use 3.14 for atb.The school wants to cover the play court with sports court flooring. Using 3.14 for, how manysquare feet of flooring does the school need to purchase to cover the play court?

Answers

The total perimeter of the court is 182.8 ft, of this, 62.8ft represents the perimeter of the semicircle.

a)

The perimeter of the semicircle is calculated as the circumference of half the circle:

[tex]P=r(\pi+2)[/tex]

Now write it for r

[tex]\begin{gathered} \frac{P}{r}=\pi \\ r=\frac{P}{\pi} \end{gathered}[/tex]

Knowing that P=62.8 and for pi we have to use 3.14

[tex]\begin{gathered} r=\frac{62.8}{3.14} \\ r=20ft \end{gathered}[/tex]

The radius of the semicircle is r=20 ft

b.

To solve this exercise you have to calculate the area of the whole figure.

The figure can be decomposed in a rectangle and a semicircle, calculate the area of both figures and add them to have the total area of the ground.

Semicircle

The area of the semicircle (SC) can be calculated as

[tex]A_{SC}=\frac{\pi r^2}{2}[/tex]

We already know that our semicircla has a radius of 10ft so its area is:

[tex]A_{SC}=\frac{3.14\cdot20^2}{2}=628ft^2[/tex]

Rectangle

To calculate the area of the rectangle (R) you have to calculate its lenght first.

We know that the total perimeter of the court is 182.8ft, from this 62.8ft corresponds to the semicircle, and the rest corresponds to the rectangle, so that:

[tex]\begin{gathered} P_T=P_R+P_{SC} \\ P_R=P_T-P_{SC} \\ P_R=182.8-62.8=120ft \end{gathered}[/tex]

The perimeter of the rectangle can be calculated as

[tex]P_R=2w+2l[/tex]

The width of the rectangle has the same length as the diameter of the circle.

So it is

[tex]w=2r=2\cdot20=40ft[/tex]

Now we can calculate the length of the rectangle

[tex]\begin{gathered} P_R=2w+2l \\ P_R-2w=2l \\ l=\frac{P_R-2w}{2} \end{gathered}[/tex]

For P=120ft and w=40ft

[tex]\begin{gathered} l=\frac{120-2\cdot40}{2} \\ l=20ft \end{gathered}[/tex]

Now calculate the area of the rectangle

[tex]\begin{gathered} A_R=w\cdot l \\ A_R=40\cdot20 \\ A_R=800ft^2 \end{gathered}[/tex]

Finally add the areas to determine the total area of the court

[tex]\begin{gathered} A_T=A_{SC}+A_R=628ft^2+800ft^2 \\ A_T=1428ft^2 \end{gathered}[/tex]

Necesito saber si los ejercicios están correctos o no y la explicación

Answers

None of the operations with radicals are correct, as two radical terms can only be added or subtracted if they have the same radical and the same exponent.

Addition and subtraction with radicals

Terms with radicals can only be added or subtracted if they have the same radical and same exponent, for example:

[tex]3\sqrt{2} + 2\sqrt{2} = 5\sqrt{2}[/tex]

In the above example, they have the same radical, of 2, and same exponent, also of 2.

The first example is given by:

[tex]7\sqrt{3} + 4\sqrt{2} = 11\sqrt{5}[/tex]

The mistake is that the two terms cannot be added, as they have different radicals, of 3 and 2.

The second example is given as follows:

[tex]3\sqrt[3]{k} - 6\sqrt{k} = -3\sqrt{k}[/tex]

The terms have the same radical, of k, but they have different exponents, of 3 and 2, hence they cannot be subtracted.

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a store donated 2 and 1/4 cases of cranes to a daycare center each case holds 24 boxes of crayons each box holds 8 crayons how many crayons did the center receive

Answers

Answer:

The center recieved 432 crayons

Explanation:

Given the following information:

There are 2 and 1/4 cases

Each case holds 24 boxes of crayons

Each box holds 8 crayons.

The number of crayons the center receive is:

8 * 24 * (2 + 1/4)

= 8 * 24 * (8/4 + 1/4)

= 192 * (9/4)

= 1728/4

= 432

The circumference of a circle is 18pi meters. What is the radius?Give the exact answer in simplest form. ____ meters. (pi, fraction)

Answers

Given:

The circumference of a circle, C=18π m.

The expression for the circumference of a circle is given by,

[tex]C=2\pi r[/tex]

Put the value of C in the above equation to find the radius.

[tex]\begin{gathered} 18\pi=2\pi r \\ r=\frac{18\pi}{2\pi} \\ r=9\text{ m} \end{gathered}[/tex]

Therefore, the radius of the circle is 9 m.

Find the solution of the system by graphing.-x - 4y=4y=1/4x-3Part B: The solution to the system,as an ordered pair,is

Answers

Solution

-x -4y = 4

y= 1/4 x -3

Replacing the second equation in the first one we got:

-x -4(1/4x -3) =4

-x -x +12= 4

-2x = 4-12

-2x = -8

x= 4

And the value of y would be:

y= 1/4* 4 -3= 1 -3= - 2

And the solution would be ( 4,-2)

Find functions f and g such that (f o g)(x) = [tex] \sqrt{2x} + 19[/tex]

Answers

We have the expression:

[tex](fog)(x)=\sqrt[]{2x}+19[/tex]

So:

[tex]g(x)=2x[/tex][tex]f(x)=\sqrt[]{x}+19[/tex]

***

Since we want to get the function g composed in the function f, and the result of this is:

[tex](fog)(x)=\sqrt[]{2x}+19[/tex]

When we replace g in f, we have to get as answer the previous expression. And by looking at it the only place where we will be able to replace values is where the variable x is located. The function f will have the "skeleton" or shape of the overall function and g will be injected in it.

From this, we can have that f might be x + 19 and g might be sqrt(2x), but the only options that are given such that when we replace g in x of f, are f = sqrt(x) + 19 and g = 2x.

The endpoints CD are given. Find the coordinates of the midpoint m. 24. C (-4, 7) and D(0,-3)

Answers

To find the coordinates of the midpoint

We will use the formula;

[tex](x_m,y_m)=(\frac{x_1+x_2}{2},\text{ }\frac{y_1+y_2}{2})[/tex]

x₁ = -4 y₁=7 x₂ = 0 y₂=-3

substituting into the formula

Xm = x₁+x₂ /2

=-4+0 /2

=-2

Ym= y₁+ y₂ /2

=7-3 /2

=4/2

=2

The coordinates of the midpoint m are (-2, 2)

Line segments, AB,BC,CD,DA create the quadrilateral graphed on the coordinate grid above. The equations for two of the four line segments are given below. Use the equations of the line segments to answer the questions that follow. AB: y = -x + 1 BC: y = -3x + 11

Answers

The equations of the line segments are,

[tex]\begin{gathered} AB\colon y=\frac{1}{3}x+1 \\ BC\colon y=-3x+11 \end{gathered}[/tex]

Calculate the equations of CD and AD.

The equation of line Cd is,

[tex]\begin{gathered} (y-(-3))=\frac{-1+3}{4+2}(x+2) \\ y+3=\frac{1}{3}(x+2) \\ 3y=x-7 \end{gathered}[/tex]

The equation of the line AD is,

[tex]\begin{gathered} y-0=\frac{-3-0}{-2+3}(x+3) \\ y=-3x-9 \end{gathered}[/tex]

1)If two lines are parallel slope will be equal and perpendicular product of slope will be -1.

From the equation, the slope of AB is 1/3

From the equation, the slope of Cd is 1/3.

So, they are parallel.

2)The slope of AB is 1/3.

The slope of BC is -3.

The product of two slopes is -1. Therefore, AB is perpendicular to BC.

3) The slope of AB is 1/3 and slope of AD is -3. Since, the product is -1, they are perpendicular.

Another pair of line segments that are perpendicular to each other is AB and AD.

Which expression is equivalent to a + 0.2c?O 1.23O 0.22O 0.2x01.023

Answers

If we have the expression:

This is the same to write:

So the answer is 1.2x.

given the residual plot below, which of the following statements is correct?

Answers

Let me explain this question with the following picture:

We can recognize a linear structure when all the points have a pattern that seems like a straight line as you can see above for example.

In the graph of your question, we can see that the points don't have a definited pattern and that's clearly not seemed like a straight line.

Therefore, the answer is option B:

There is not a pattern, so the data is not linear.

-Jun 18 of
Find the domain and the range of the given relation.
{(6,8), (-3,4), (-1,-6), (-6, -1)}

Answers

Domain: [-6, -3, -1, 6]
Range: [-6, -1, 4, 8]

Simplify the expression leave expression in exact form with coefficient a and b so we have a✔️b.

Answers

coefficient of a = 2x

Explanation:[tex]\text{The expression: 2}\sqrt[]{x^2y}[/tex]

Simplifying:

[tex]\begin{gathered} \sqrt[]{x^2}\text{ = x} \\ 2\sqrt[]{x^2\times y}\text{ = 2x}\sqrt[]{y} \end{gathered}[/tex]

Since we are told the coefficient of a can be the product of a number and variable:

[tex]\begin{gathered} 2x\sqrt[]{y}\text{ is in the form a}\sqrt[]{b} \\ a\text{ = 2x},\text{ b = y} \\ 2\text{ = number, x = variable} \\ 2x\text{ = product of number and variable} \\ \text{coefficient of }a\text{ = 2x} \end{gathered}[/tex]

The schedule for summer classes is available and Calculus and Introduction to Psychology are scheduled at the same time, so it is impossible for a student to schedule for both courses. The probability a student registers for Calculus is 0.05 and the probability a student registers for psychology is 0.62. What is the probability a student registers for Calculus or psychology?

Answers

Explanation

The given is that the probability a student registers for Calculus is 0.05 and the probability a student registers for psychology is 0.62. Since it impossible for a student to schedule for both courses, we will have

[tex]\begin{gathered} Pr(Psychology\text{ or calculus\rparen=Pr\lparen P\rparen+Pr\lparen C\rparen-Pr\lparen P}\cap C) \\ =0.05+0.62-0 \\ =0.67 \end{gathered}[/tex]

Answer: 0.67

After knee surgery, your trainer tells you to return to your jogging program slowly. He suggests you start by jogging for 14 minutes each day. Each week after, he suggests that you increase your daily jogging time by 7 minutes. How many weeks before you are up to jogging 70 minutes?

Answers

Given that initial time for jogging is,

[tex]a_{_1}=14[/tex]

After each week the time is increased by

[tex]d=7[/tex]

This gives an arithmetic sequence.

To find n such that,

[tex]a_n=70[/tex]

Therefore,

[tex]\begin{gathered} a_n=a_1+(n-1)d \\ n=\frac{a_n-a_1}{d}+1 \end{gathered}[/tex]

So,

[tex]\begin{gathered} n=\frac{70-14}{7}+1 \\ =\frac{56}{7}+1 \\ =8+1 \\ =9 \end{gathered}[/tex]

Therefore, 9 weeks before you are up to jogging 70 minutes.

Find the length of the rectangle pictured above, if the perimeter is 82 units.

Answers

The formula for determining the perimeter of a rectangle is expressed as

Perimeter = 2(length + width)

From the information given,

width = 16

Perimeter = 82

Thus, we have

82 = 2(length + 16)

By dividing both sides of the equation by 2, we have

82/2 = 2(length + 16)/2

2 cancels out on the right side of the equation. We have

41 = length + 16

length = 41 - 16

length = 25

What does "equidistant” mean in relation to parallel lines?O The two lines lie in the same plane.The two lines have the same distance between them.The two lines go infinitely.The two lines have an infinite number of points.

Answers

we have that

parallel lines (lines that never intersect) are equidistant in the sense that the distance of any point on one line from the nearest point on the other line is the same for all points.

therefore

the answer is

The two lines have the same distance between them.

Anna's goal is to raise more than $200 for a
charity. Three of her neighbors donated $15 each, and one of her
friends donated $5. Write an inequality to show how much more
money Anna needs to raise. Explain how you found the answer.
Tell why you chose the inequality symbol that you used.

Answers

225 dollars because you have to multiply 45 times 5

Answer: 200 < 50 + x

Step-by-step explanation:

Since three of her neighbors donated 15 dollars each, we can find how much she earned from them by doing 3 x 15 = 45.

Including the 5 dollars earned by her friend, we get 50 dollars by doing 45+5 = 50.

Anna needs more than 200 dollars so 200 has to be less than Anna's total earnings. (x) is how much more Anna will need to earn to make the inequality true.

Austin walks 3.5km every day. How far does he walk in 7 days?Write your answer in meters.

Answers

Answer:

24,500 meters

Step-by-step explanation:

Given the matrices A and B shown below, find – į A+ B.89A=12 4.-4 -10-6 12B.=-3-19-10

Answers

Given:

[tex]\begin{gathered} A=\begin{bmatrix}{12} & {4} & {} \\ {-4} & {-10} & {} \\ {-6} & {12} & {}\end{bmatrix} \\ B=\begin{bmatrix}{8} & {9} & {} \\ {-3} & {-1} & {} \\ {-9} & {-10} & {}\end{bmatrix} \end{gathered}[/tex]

Now, let's find (-1/2)A.

Each term of the matrix A is multiplied by -1/2.

[tex]\begin{gathered} \frac{-1}{2}A=\frac{-1}{2}\begin{bmatrix}{12} & {4} & {} \\ {-4} & {-10} & {} \\ {-6} & {12} & {}\end{bmatrix} \\ =\begin{bmatrix}{\frac{-12}{2}} & {\frac{-4}{2}} & {} \\ {\frac{4}{2}} & {\frac{10}{2}} & {} \\ {\frac{6}{2}} & {-\frac{12}{2}} & {}\end{bmatrix} \\ =\begin{bmatrix}{-6} & {-2} & {} \\ {2} & {5} & {} \\ {3} & {-6} & {}\end{bmatrix} \end{gathered}[/tex]

Now let's find (-1/2)A+B.

To find (-1/2)A+B, the corresponding terms of the matrices are added together.

[tex]\begin{gathered} \frac{-1}{2}A+B=\begin{bmatrix}{-6} & {-2} & {} \\ {2} & {5} & {} \\ {3} & {-6} & {}\end{bmatrix}+\begin{bmatrix}{8} & {9} & {} \\ {-3} & {-1} & {} \\ {-9} & {-10} & {}\end{bmatrix} \\ =\begin{bmatrix}{-6+8} & {-2+9} & {} \\ {2-3} & {5-1} & {} \\ {3-9} & {-6-10} & {}\end{bmatrix} \\ =\begin{bmatrix}{2} & {7} & {} \\ {-1} & {4} & {} \\ {-6} & {-16} & {}\end{bmatrix} \end{gathered}[/tex]

Therefore,

[tex]undefined[/tex]

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A marble was thrown vertically up the air and came back down to the samelevel in 1.6 s. (using g = 9.81 ms?).(a) What is it initial velocity?(b) What would be the highest height it can reach?(c) How long would it take to reach the highest point? an assembly line requires two components: gadjits and widjits. gadjits are produced by center 1 and widjits are produced by center 2. each unit of the end item, called a jit-together, requires 3 gadjits and 2 widjits. the daily production quota on the assembly line is 900 jit-togethers. the container for gadjits holds 90 units. the policy variable for center 1 is set at 0.04. the average waiting time for a container of gadjits is 0.07 day, and 0.07 day is needed to produce a container. the container for widjits holds 50 units, and the policy variable for center 2 is 0.07. the average waiting time per container of widjits is 0.12 day, and the time required to process a container is 0.26 day. how many containers are needed for gadjits? and how many containers are needed for widjits? What is 1 way to make the operational definition, "on a cold day", better? "On a cold day, determine what happens to a can of soda left outside." which of the following would most likely have caused the production possibilities frontier to shift outward from a to b? group of answer choices a decrease in unemployment a technological advance in the consumer goods industries a general technological advance an increase in the availability of capital-producing resources prove the formula sin 3 A + sin A = 4 sin A cos2A A group of people were asked if they owned a dog. 191 responded "yes", and 485 responded "no".Find the probability that if a person is chosen at random, they own a dog. 191485 294191 191676 suppose that the members of a student governance committee will be selected from the 40 members of the student senate. there are 18 sophomores, 12 juniors and 10 seniors who are members of the student senate. in how many ways can the governance committee be selected, if it must be made up of 2 sophomores, 2 juniors and 3 seniors? assume that each of the sophomores, each of the juniors and each of the seniors is equally likely to be selected for the committee. a. 339 b. 1211760 c. 2160 d. 18643560 e. 25920 The graph shows a dilation of trapezoid TRAP with respect to the origin which statements are true about the figures select three complete the table to show the total change in the average mean daily in the price of for stocks over a five-day. 1. Why does Friar Lawrence seem so uneasy about Paris's request? A parallelogram has an area of 364.5 cm2. If the base is 27 cm, What is the height? Jim baked 48 cookies with 4 scoops of flour. How many scoops of flour does Jim need in orderto bake 96 cookies? Assume the relationship is directly proportional. what would happen if there was no greenhouse effect within Earth's atmosphere? Alyssa will correctly label the numbers 48.4, 48482, 48.09, and 48on the number line below. Fill in the missing number to complete the linear equation that gives the rule for this tablex: 4, 5, 6, 7y: 32, 40, 48, 56y = ?x NOBODY'S ANSWERING MY QUESTION, HELLO? I WILL GIVE BRAINLIEST :( how many shirts can Jeanette sew at most of and still have 1. spool of thread left helpppppppppppppppppppppppppppppp an off-shore windfarm is likely coming to north carolina, and beachfront property owners are concerned about potential property value impacts. to monetize these impacts, one could use the nonmarket valuation technique. select one: a. averting behavior. b. travel cost. c. hedonic. d. contingent valuation. why are mhc molecules able to bind a variety of peptides? 1. the peptide-binding groove of a specific mhc molecule can bind several peptides simultaneously 2. the mhc genes undergo somatic recombination to produce thousands of mhc molecule variants 3. mhc bind very loosely and transiently to peptide antigens, so a wide variety of peptide antigens can bind any specific mhc molecule 4. a small number of amino acids in the peptide antigen bind specifically to complementary pockets in the mhc molecule binding groove