Answer:
Step-by-step explanation:
2
3x + y =-12x
Answer:
Step-by-step explanation:
y= 2
45−6x
2−3 y=
2− 45−6x
2 −3 , ∣x∣≤ 2
30
Can someone please help answer this question on simultaneous equations?
Answer:
1 knife cost £6.6
Step-by-step explanation:
Simultaneous equation is;
4x = y ----------(equation 1)
12y + 16x = 105.64 ----------- (equation 2)
Rewrite equations:
4x=y;16x+12y=105.64
Step: Solve4x=yfor y:
4x=y
4x+−y=y+−y(Add -y to both sides)
4x−y=0
4x−y+−4x=0+−4x(Add -4x to both sides)
−y=−4x
−y/−1 = −4x/−1
(Divide both sides by -1)
y=4x
Step: Substitute 4x for y in 16x+12y=105.64:
16x+12y=105.64
16x+124x=105.64
64x=105.64(Simplify both sides of the equation)
64x/64 = 105.64/64
(Divide both sides by 64)
x=1.650625
Step: Substitute 1.650625 for x in y=4x:
y=4x
y=(4)(1.650625)
y=6.6025(Simplify both sides of the equation)
1 knife cost = 4x = 4(1.65) = 6.6
∴ 1 knife cost £6.6
Suppose the function f and g are defined as follows.
In this session we will focus on calculating the composition of f and f.
given the function f, the composition f composition f is obtained by taking the definiton of f and replace the varaible x with the function f itself. So we are given that
[tex]f(x)=\frac{8}{5x}[/tex]So
[tex]f\circ f(x)=\frac{8}{5(\frac{8}{5x})}=\frac{8}{\frac{8}{x}}=\frac{8x}{8}=x[/tex]So we have that f composition f is the function x.
consider the following basket of goods: 15 lollipops, 10 bars of chocolate, four jars of peanut butter, and two ice-cream cakes. suppose that in 1999, each lollipop was 10 cents, each bar of chocolate was $1.50, each jar of peanut butter was $2.50, and each ice-cream cake was $7.99. in 2018, each lollipop was 80 cents, each bar of chocolate was $3.75, each jar of peanut butter was $4.25, and each ice-cream cake was 12.99. what was the value of the basket in 2018?
The value of the basket in 2018 was $92.48 if the basket contains 15 lollipops, 10 bars of chocolate, four jars of peanut butter, and two ice-cream cakes.
The value of the basket in 2018 can be calculated by using multiplication and addition.
First, we multiply the cost of each good in 2018 by the number of that good in the basket to calculate their total cost.
Lollipop: $0.80 × 15 = $12
Chocolate: $3.75 × 10 = $37.5
Peanut butter: $4.25 × 4 = $17
Ice-cream cake: $12.99 × 2 = $25.98
Now the value of the basket in 2018 can be calculated by adding these amounts of each good. Therefore;
Value of basket = $12 + $37.5 + $17 + $25.98
Value of basket = $92.48
Hence the value of the basket in 2018 is $92.48
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whats the answer? one angle of a triangle mesuares 98°. the other two angles are congruent. enter and solve an equation to find the mesuare x of the congruent angles.
Congruent angles simply means angles that are equal. A triangle has three angles . Since one of the angle is given as 98 degree, the other 2 angles which are congruents are therefore equal. The total angle of a triangle is equals to 180 degree. Therefore,
[tex]\begin{gathered} x+x+98=180 \\ 2x+98=180 \\ 2x=180-98 \\ 2x=82 \\ x=\frac{82}{2} \\ x=41 \end{gathered}[/tex]x = 41 degree
Steve stopped for a drink of water when he had completed 60% of his jog. He had traveled 3 miles. What is the total distance Steve jogged?
2 miles
3 miles
4 miles
5 miles
6 miles
The total distance Steve jogged is 5 miles.
what is percent?The Latin word "per centum," which meaning "by the hundred," was the source of the English word "percentage." Fractions with a denominator of 100 are called percentages. In other words, it is a relationship where the value of the entire is always assumed to be 100.
A percentage is a ratio or fraction where the full value is always 100. Sam, for instance, would have received 30 out of a possible 100 points if he had received 30% on his arithmetic test. In ratio form, it is expressed as 30:100 and in fraction form as 30/100.
Given:
Steve completed 60% of the Jog.
Also, he travelled 3 miles.
Let the total distance he travelled be x miles.
Then,
60% of x =3
60/100 x= 3
x= 3 x 100 / 60
x= 300/60
x= 5 miles.
Hence, total he had to jog 5 miles.
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separate 84 into two parts such that one part will be 12 less than twice the other
Answer:
32, 52
Step-by-step explanation:
84=x+y
x=2y-12
Solving the system of equations
Plug second equation into first
84=(2y-12)+y
84=3y-12
y=32
Plug y into first equation
84=x+32
x=52
Determine the midpoint of segment Ed coordinates e and d are 2 and -2
Answer: Midpoint = 0
Explanation:
The midpoint of segment ED can be calculated as:
[tex]\text{Midpoint}=\frac{E+D}{2}[/tex]Where E and D are the coordinates of E and D respectively.
So, replacing E by 2 and D by -2, we get:
[tex]\text{MIdpoint}=\frac{2+(-2)}{2}=\frac{2-2}{2}=\frac{0}{2}=0[/tex]Therefore the midpoint of segment ED is equal to 0.
Please can someone help solve the attached:
The translation moves 5 units to the left and 2 units down, so we have:
c = -5
d = -2
How to find the values of C and D?To identify the translation, let's follow a single vertex of the triangle.
The top vertex of triangle A is at (2, -3)
After a reflection about the x-axis only the y-value changes, so after the reflection the coordinates of that vertex will be:
(2, 3).
In now we apply the given translation, the new coordinates will be:
(2 + c, 3+ d)
And the coordinates of this vertex on triangle B is (-3, 1), so we have:
(2 + c, 3+ d) = (-3, 1)
2 + c = -3
c = -3 - 2 = -5
3 + d = 1
d = 1 - 3
d = -2
So the translation is defined by the values:
c = -5
d = -2
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What four consecutive integers have a sum of 86. Name them
The four consecutive integers are 20, 21, 22, and 23 whose sum is 86.
What do you mean by integer no?using sequential means.
Integers are a collection of whole integers and their antipodes, such as -3, -2, 1, 0, 1, 2, 3, etc.
86 is obtained by adding together the four consecutive integers x, (x+1), (x+2), and (x+3)
x + (x+1), (x+2), and (x+3) = 86
the smallest one, x, is now solved for: 4x + 6 = 86
The numbers are 20, 21, 22, and 23, because 4x = 80 x = 20.
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Answer:
20, 21, 22 & 23
Step-by-step explanation:
Forming the equation,
→ x + (x + 1) + (x + 2) + (x + 3) = 86
→ 4x + 6 = 86
Now the the value of x will be,
→ 4x + 6 = 86
→ 4x = 86 - 6
→ x = 80/4
→ [ x = 20 ]
Then the required numbers will be,
→ x = 20
→ x + 1 = 20 + 1 = 21
→ x + 2 = 20 + 2 = 22
→ x + 3 = 20 + 3 = 23
Hence, numbers are 20, 21, 22, 23.
Solve the following inequality.xe^x ≥7Choose one:1. x ≤ 1.522. no solution3. x ≤ 1.954. x ≥ 1.955. x ≥ 1.52
1) Considering e =2.72
Then let's plug it in the inequality, and calculate the natural logarithm.
[tex]\begin{gathered} xe^x\ge7 \\ x2.72^x\ge7 \\ 2.72^x\ge\frac{7}{x}^{} \\ \ln 2.72^x\ge\ln (\frac{7}{x}) \\ x\text{ }\ge1.52 \end{gathered}[/tex]2) Then option 5 is the answer
X≥ 1.52
a) Write 98 as the product of prime factors. Write the prime factors in ascending order.
Step-by-step explanation:
Write 98 as the product of prime factors. Write the prime factors in ascending order.
2 × 7 × 7
2 × 7 × 7 = 98
Answer: 2×7×7
Step-by-step explanation: 98= 2×7×7
Lets first know about what is prime factor :- A factor which is a Prime number and not a composite number.
prime factor in ascending order = 2,7
hence the required product of prime factor is 2×7×7 or 2×[tex]7^{2}[/tex]
Four friends want to share a package of cookies with m number of cookies in it which expression represents the numbers of cookies each friends will get
Based on the case, we know that four friends want to share their cookies package. The number of the cookies is represent by 'm'. So, how many part for each friends will get?
We can solve the case by 'fraction'. Fractions represent the parts of a whole objects. A fraction is arranged by two parts. First, numerator is the number on the top of the line. Basically, numerator is how many equal parts of the whole objects are taken. Second, denominator is the number below the line. In the other word, denominator is the total number.
If four friends want to share the whole package of cookies, is means that the package will be divided to 4 parts. The whole part is represented by 'm'. So, the fraction form that can describe this case is each friends will get [tex]\frac{1}{4}[/tex] m.
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Harley rides her bicycle the same distance every day for 4 days. The total distance she rides is 814 miles. How many miles does she ride each day?
Answer:
203.5
Step-by-step explanation:
just divide 814 by 4
Answer:
203.5 miles per day
Step-by-step explanation:
divide 814 by 4= 203.5
Identify a set of parallel and a set of perpendicular lines in this image.
m
B
LL
OBFCG, BF 1 CG
OBECG, AD 1 EH
O AD
EH, EHL BE
O AD EH, BF 1 CG
A set of parallel lines and a set of perpendicular lines are: BF║CG, AD⊥BF.
What are Parallel Lines?Parallel lines are straight lines that are of equal distance at every point away from each other, and therefore, do not intersect each other at any point. The sign "║" is used to indicate that two lines are parallel lines.
What are Perpendicular Lines?Lines that are said to be perpendicular lines are lines that intersect each other at right angle or 90 degrees. That is, at the point of their intersection, a right angle is formed which is 90 degrees. The sign "⊥" is used to indicate that two lines are perpendicular lines.
In the image given, lines BF and CG do not intersect at any point and they are of equal distance away from each other at every point, therefore, CG and BF are perpendicular lines.
Also, we can see that a right angle is formed at the point of intersection of lines AD and BF, therefore AD and BF are perpendicular lines.
Thus, we can state that: BF║CG, AD⊥BF.
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Which of the following is an example of a set of like terms ??
2. >>>>>>>b {18x,-x,21x} is an example of like terms because they both hold the same variables.
4.>>>>>>
[tex] = - 7(2x - 3) \\ = - 7(2x) - 7( - 3) \\ = - 14x + 21[/tex]
ATTACHED IS THE SOLUTION
How is adding positive and negative integers different from adding only positive integers on a number line?
1) To understand how that works, let me draw a number line:
If we only add positive numbers like 2 +3 = 5, 6+8 =14, etc. we'll only get a positive result (right to the zero) on the number line, we are moving to the right
2) If we add positive and negative numbers, for example:
2 +(-3) =2 -3=-1
0+(-1)= -1
6+(-2)= 4
On the number line, we are starting from one point and moving to the left.
a company buys equal numbers of two different card forms. it utilizes 4/5 of one kind and 6/7 of the other. what fraction of the total number is unused?
12/35 fraction of the total number is unused from two different cards.
What is a fraction?A fraction is written in the form of p/q, where q ≠ 0.
Fractions are of two types they are proper fractions in which the numerator is smaller than the denominator and improper fractions where the numerator is greater than the denominator.
Assuming the total first kind of card form is 1 and the total second kind of card form is also one.
Given, a company buys equal numbers of two different card forms. it utilizes 4/5 of one kind and 6/7 of the other.
∴ The total unused card form is,
= (1 + 1) - (4/5 + 6/7).
= 2 - (28 + 30)/35.
= 2 - 58/35.
= (70 - 58)/35.
= 12/35.
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Low flow showerheads use 2 1/2 gallons of water per minute. If family members shower a total of 2 1/3 hours per week, how much water does the family use for showers each week? Write an expression that represents the problem. Then solve the problem.
The expression that represents the situation is 5/2(x) and the family uses 350 gallons of water for each week.
Showerheads:
The showerhead is a bathroom fixture that directs the flow of water in a bathroom shower.
Given,
Low flow showerheads use 2 1/2 gallons of water per minute.
And the family uses 2 1/3 hours per week.
Here we need to find the expression for this situation and we also need to find the amount of water used by the family.
First, we have to convert the mixed fraction into improper fraction, then we get,
2 1/2 =5/2
So, for one minute the showerhead use 5/2 gallon of water.
So, the expression for this situation is,
=> 5/2(x).
Where x represents the amount of time in minutes.
Now, we know that the family uses the showerhead for 2 1/3 hours per week.
So, we have to convert this mixed fraction into improper fraction,
2 1/3 = 7/3
We know that, 1 hour = 60 minutes.
So, 7/3 hours is equal to,
=> 7/3 x 60 = 7 x 20 = 140
Then, the amount of water used by the family is,
=> 5/2 (140)
=> 5 x 70
=> 350
Therefore, the amount of water used by the family is 350 gallons per week.
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Angle P in Triangle PQR has the same measure as Angle S in Triangle STU. Which other condition is necessary to prove that these triangles are similar?
△PQR is congruent to △STU (△PQR ≅ △STU) under ASA condition using options (B) and (D).
What is the congruency of triangles?Triangle congruence: If all three corresponding sides and all three corresponding angles are equal in size, two triangles are said to be congruent. Slide, rotate, flip, and turn these triangles to create an identical appearance. They are in alignment with one another when moved. Therefore, if all three sides of two triangles are the same, then the triangles are said to be congruent. If we have a side, an angle between the sides, and then another side that is congruent, we know they are congruent. In other words, side, angle, side.So, to prove that △PQR ≅ △STU:
∠P = ∠S (Given)PQ = ST (Option B)∠Q = ∠T (Option D)So, with these three conditions, △PQR ≅ △STU is under ASA condition.
Therefore, △PQR is congruent to △STU (△PQR ≅ △STU) under ASA condition using options (B) and (D).
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11. FINANCIAL LITERACY The surf shop has a weekly overhead of $2300. b. How many skimboards and longboards must the shop sell each week to make a profit a. Write an inequality to represent the number of skimboards and longboards the shop sells each week to make a profit.
Skimboard costs 115 longboard costs 685
x square root 7x + 10
factor the equation
algerbra 2
Answer:
Step-by-step explanation:
x
=
−
2
x
=
−
5
Explanation:
x
2
+
7
x
+
10
=
0
We could right the equation in another form using brackets.
(
x
+
2
)
(
x
+
5
)
=
0
In order to get two numbers to multiply and give 0, at least one number has to be 0.
a stands for the first bracket and b for the second.
a x b = 0
a=0 or b=0 to make this equation valid.
Therefore x= -2 or x= -5 because -2+2=0 and -5+5=0 according to both brackets.
Please help me with 24For the following exercises, write the equation for the hyperbola in standard form if it is not already, and identify the vertices and foci, and write equations of asymptotes.
Given the equation,
[tex]-9x^2+72x+16y^2+16y+4=0[/tex]Complete squares as shown below,
[tex]\begin{gathered} -9x^2+72x-a^2=-(9x^2-72x+a^2)=-9(x^2-8x+b^2) \\ \end{gathered}[/tex]Thus,
[tex]\begin{gathered} \Rightarrow-9x^2+72x-a^2=-9(x^{}-4)^2 \\ \Rightarrow a^2=16\cdot9=144\Rightarrow a=12 \\ \Rightarrow-9x^2+72x-144=-9(x^{}-4)^2 \end{gathered}[/tex]Similarly,
[tex]\begin{gathered} 16y^2+16y=16(y^2+y) \\ \Rightarrow16(y+\frac{1}{2})^2=16(y^2+y+\frac{1}{4}) \end{gathered}[/tex]Therefore,
[tex]\begin{gathered} -9x^2+72x+16y^2+16y+4=0 \\ \Rightarrow-9(x-4)^2+16(y+\frac{1}{2})^2+4=-144+4 \\ \Rightarrow-9(x-4)^2+16(y+\frac{1}{2})^2=-144 \end{gathered}[/tex]Finally, the standard form is.
[tex]\begin{gathered} \Rightarrow-\frac{(x-4)^2}{16}+\frac{(y+\frac{1}{2})^2}{9}=-1 \\ \Rightarrow\frac{(x-4)^2}{16}-\frac{(y+\frac{1}{2})^2}{9}=1 \end{gathered}[/tex]As for the vertices, foci, and asymptotes,
[tex]\begin{gathered} c=\pm\sqrt[]{16+9}=\pm5 \\ \text{center:}(4,-\frac{1}{2}) \\ \Rightarrow\text{foci:}(4-5,-\frac{1}{2})_{},(4+5,-\frac{1}{2})_{} \\ \Rightarrow\text{foci:}(-1,-\frac{1}{2}),(9,-\frac{1}{2}) \end{gathered}[/tex]Foci: (-1,-1/2), (9,-1/2)
Vertices
[tex]\begin{gathered} \text{center:}(4,-\frac{1}{2}),\text{vertices:}(4\pm a,-\frac{1}{2}) \\ \text{vertices:}(4+4,-\frac{1}{2}),(4-4,-\frac{1}{2}) \\ \text{vertices:}(8,-\frac{1}{2}),(0,-\frac{1}{2}) \end{gathered}[/tex]Vertices: (8,-1/2), (0,-1/2)
Asymptotes:
[tex]\begin{gathered} y=\pm\frac{3}{4}(x-4)-\frac{1}{2} \\ \Rightarrow y=\frac{3}{4}x-\frac{7}{2} \\ \text{and} \\ y=-\frac{3}{4}x+\frac{5}{2} \end{gathered}[/tex]Asymptotes: y=3x/4-7/2 and y=-3x/4+5/2
Sergio wants to hand a 40 1/2 inch by 28 2/3 inch canvas painting on a wall in his room. The width of the wall is 15 2/3 feet. The height of the wall is 3/4 the width of the wall. a. What is the area of the wall? b. How much of the wall will be uncovered after Sergio hangs the painting?
The most appropriate choice for area of rectangle will be given by-
a) Area of the wall = [tex]26508[/tex] [tex]in^2[/tex]
b) Area of wall left uncovered = [tex]25347[/tex] [tex]in^2[/tex]
What is area of rectangle?
Area of rectangle is the total space taken by the rectangle. If l is the length of the rectangle and b is the breadth of the rectangle, then area of the rectangle is given by
Area = [tex]l \times b[/tex]
Here,
Width of the wall = [tex]15\frac {2}{3}[/tex] feet = [tex]\frac{47}{3}[/tex] feet
Height of the wall = [tex]\frac{3}{4} \times \frac{47}{3}[/tex] feet
= [tex]\frac{47}{4}[/tex] feet
a) Area of the wall = [tex]\frac{47}{3} \times \frac{47}{4}[/tex] [tex]ft^2[/tex]
=[tex]\frac{2209}{12} \times 12 \times 12[/tex] [tex]in^2[/tex]
= [tex]26508[/tex] [tex]in^2[/tex]
b) Length of painting = [tex]40 \frac{1}{2}[/tex] in = [tex]\frac{81}{2}[/tex] in
Breadth of painting = [tex]28\frac{2}{3}[/tex] in = [tex]\frac{86}{3}[/tex] in
Area of painting = [tex]\frac{81}{2} \times \frac{86}{3}[/tex] [tex]in^2[/tex]
= [tex]1161[/tex] [tex]in^2[/tex]
Area of wall left uncovered = (26508 - 1161) [tex]in^2[/tex]
= 25347 [tex]in^2[/tex]
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find the zeros of the function and state the multiplicities
Answer:
x = -3/4, x = 0, x = 5
Explanation:
The equation can be rewritten as
[tex]m(x)=x(12x^2-51x-45)[/tex]The roots are found by equating the above to zero:
[tex]x(12x^2-51x-45)=0[/tex]One root we immediately notice is x = 0. The other roots are found using the fact that
[tex]12x^2-51x-45=0[/tex]To solve for x we use the quadratic formula which says for
[tex]ax^2+bx+c=0[/tex]the x is given by
[tex]undefined[/tex]The number 24 is 4 times as many as 6.
Write this comparison as a multiplication equation.
+
Compare with multiplication
Jessy is looking to subscribe to seventeen magazine for fashion inspiration. Before registering Jessy wants to make sure this is within her budget. Jessy knows there is an initial sign-up fee and a monthly payment required for the subscription. If the monthly subscription fee is $10 and Jessy remembers having a ball on the 2nd month for $26 write an equation that represents the total cost of subscribing to seventeen magazine.
jerry purchased a single family lot that measured 90' x 120'. the city requires a 20' setback on the front, a 15' setback along the sides and a 10' setback at the back of the lot. how big can jerry build his house?
The best measure of how big Jerry can build his house as required in the task content is; 60' by 90'.
Dimensions.It follows from the task content that the dimension of the family lot purchased by Jerry in a bid to build his house has dimensions; 90' × 120'.
Since the city requires 20' setback on the front and 10' setback at the back, it follows that the vertical length remaining and available to build his house is; 120' - 20' - 10' = 90'.
Also, the horizontal width available for him to build his house after the 15' setback along the sides is; 90' - 15' - 15' = 60'.
Therefore, the space available for Jerry to.build his house is; 60' × 90'.
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if one shirt costs £13,how many can I buy with £419?
Answer:
32 shirts
Step-by-step explanation:
419÷13
=32.230
Answer:
32
Step-by-step explanation:
419 divided by 13
= 32.230
Graph the image of the figure on the right under the given translation.T(3, -1) (x,y)
Answer:
The only image with edges at the given coordinates is;
Given the figure in the attached image.
we want to identify the image after a translation;
[tex]T(3,-1)(x,y)[/tex]Using one of the edges of the figure;
[tex](x,y)=(-4,0)[/tex]Applying the above translation we have;
[tex](-4,0)\rightarrow(-4+3,0-1)=(-1,-1)[/tex]The edge of the image would be at;
[tex](-1,-1)[/tex]Therefore, the only image with edges at the given coordinates is;
3. Suppose that the scores on a statewide standardized test are normally distributed with a mean of 69 and a standard deviation of 6. Estimate the percentage of scores that were(a) between 57 and 81. %(b) above 81. %(c) below 63. %(d) between 51 and 81. %
Answer:
a) 95%
b) 2%
c) 16%
d) 98%
Explanation:
We have the following:
This is a normal distribution
Mean = 69
Standard Deviation = 6
a) Between 57 and 81%
[tex]\begin{gathered} z=\frac{x-\mu}{\sigma} \\ x=57 \\ z=\frac{57-69}{6}=-\frac{12}{6} \\ z=-2 \\ \\ x=81 \\ z=\frac{81-69}{6}=\frac{12}{6} \\ z=2 \\ \end{gathered}[/tex]The probability that a score is between 57 & 81 is given by the Area between (z = -2) & (z = 2):
[tex]\begin{gathered} P=0.97725-0.02275 \\ P=0.9545 \\ P=95.45\approx95 \\ P=95\text{ \%} \\ \\ \therefore P=95\text{ \%} \end{gathered}[/tex]b) Above 81%
[tex]\begin{gathered} z=\frac{x-\mu}{\sigma} \\ x>81 \\ z=\frac{81-69}{6} \\ z=\frac{12}{6}=2 \\ z=2 \end{gathered}[/tex]The probability that a score is above 81% is given by the area of the graph greater than (z = 2):
[tex]\begin{gathered} P=0.02275 \\ P=2.275\approx2.3 \\ P=2.3\approx2 \\ P=2\text{ \%} \\ \\ \therefore P=2\text{ \%} \end{gathered}[/tex]c) Below 63%
[tex]\begin{gathered} x<63 \\ z=\frac{63-69}{6} \\ z=-\frac{6}{6}=-1 \\ z=-1 \end{gathered}[/tex]The probability that a score is below 63% is given by the area of the graph lesser than (z = -1):
[tex]\begin{gathered} P=0.15866 \\ P=15.866\approx16 \\ P=16\text{ \%} \end{gathered}[/tex]d) Between 51 and 81
[tex]\begin{gathered} 51\le x\le81 \\ z=\frac{51-69}{6} \\ z=-\frac{18}{6}=-3 \\ z=-3 \\ \\ z=\frac{81-69}{6} \\ z=\frac{12}{6}=2 \\ z=2 \end{gathered}[/tex]The probability that a score is between 51 & 81 is given by the Area between (z = -3 & (z = 2):
[tex]\begin{gathered} P=0.97725-0.00135 \\ P=0.9759 \\ P=97.59\approx98 \\ P=98\text{ \%} \end{gathered}[/tex]