Mathematics, 03.07.2020 23:01 ruben0018

IQ scores are normally distributed with a mean of 100 and a standard deviation of 15. What percentage of people have an IQ score between 69 and 132, to the nearest tenth?

Answers: 3

Show answers

Answers

Answer from: gamergladiator43

96.4% of people have an IQ score between 69 and 132

Step-by-step explanation:

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question:

$\mu = 100, \sigma = 15$

What percentage of people have an IQ score between 69 and 132, to the nearest tenth?

The proportion is the pvalue of Z when X = 142 subtracted by the pvalue of Z when X = 69. The percentage is the proportion multiplied by 100. So

X = 132

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{132 - 100}{15}$

Z = 2.13

Z = 2.13 has a pvalue of 0.983

X = 69

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{69 - 100}{15}$

Z = -2.07

Z = -2.07 has a pvalue of 0.019

0.983 - 0.019 = 0.964

0.964*100 = 96.4%

96.4% of people have an IQ score between 69 and 132

Answer from: Quest

first anwser choice.

step-by-step explanation:

the greater/less or equal to symbol (> or < with the line at the bottom) is a closed/filled in circle.

when multiplying or dividing by a negative on both sides you have to flip the inequality sign. this rule only applies to multiplying or dividing by a negative number in inequality equations. this rule is really important.

-5c + 2 _< _27

subtract from both sides by 2

-5c _< _ 27

divide both sides by -5

c _< _ 5.4

flip the inequality sign

c _> _5.4

the only possible answer that would match the simplified inequality is the first answer choice

5c+2< 27 i really do not understand this.

Answer from: Quest

-3

step-by-step explanation:

a drawing really does here:

so i draw the horizontal line y=2 and the vertical line x=-2 at this intersection i put b (this is where my right angle is going to be). so point b is at (-2,2). point a is 5 units long and is also on y=2 so this point has to be (3,2) or (-7,2) -doesn't matter i will go with (3,2).

now we know c is at (-2,y) we don't know the y yet bet we know that c is on x=-2.

we have the area of the triangle is .5bh=12.5

we know the base length is 5 (ab)

we have the height is (2-y) if you look at your

plug in

.5(5)(2-y)=12.5

solve for y to get the y-coordinate for c

2.5(2-y)=12.5

divide both sides by 2.5 giving:

2-y=5

now subtract 2 on both sides

-y=3

y=-3

Another question on Mathematics

Mathematics, 21.06.2019 13:00

What is the least common multiple of 16 and 3?

Answers: 2

Answer

Mathematics, 21.06.2019 19:10

Do more republicans (group a) than democrats (group b) favor a bill to make it easier for someone to own a firearm? two hundred republicans and two hundred democrats were asked if they favored a bill that made it easier for someone to own a firearm. how would we write the alternative hypothesis?

Answers: 1

Answer

Mathematics, 21.06.2019 19:30

In the given triangle, ∠aed ∼ ∠ abc, ad = 6.9, ae = 7.2, de = 5.2, and bc = 10.2. find the measure of bd and ce. round your answer to the nearest tenth.

Answers: 2

Answer

Mathematics, 21.06.2019 20:50

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c

Answers: 3

Answer

You know the right answer?

IQ scores are normally distributed with a mean of 100 and a standard deviation of 15. What percentag...

Questions