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3 years ago

The scores on a test given to all juniors in a school district are normally distributed with a mean of 75 and a standard deviati

on of 7.
Find the percent of juniors whose score is no more than 89.

The percent of juniors whose score is 89 or below is ___%

Mathematics

1 answer:

marta [7]3 years ago

3 0

$\mathbb P(X\le89)=\mathbb P\left(\dfrac{X-75}7\le\dfrac{89-75}7\right)=\mathbb P(Z\le2)\approx0.9773=97.73\%$

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Paige lives 3 miles east of her school. Diego lives & miles west of the school

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Step-by-step explanation:

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3 years ago

Please answer 3! Thanks

melamori03 [73]

You need to do 175 divided by 3.

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3 years ago

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On saturdays, elliott practises the piano, walks his dog, does his homework, and cleans his room. use an organized list to show

puteri [66]

The possible orders in which Elliott can do these tasks is 24

<h3>What is Permutation ?</h3>

Permutation is defined as the number of ways r number of objects can be arranged in total n number of objects.

P(n,r) = n! / (n-r)!

As Elliot have 4 tasks to do practices the piano (A), walks his dog(B), does his homework(C), and cleans his room(D)

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brainly.com/question/1216161

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1 year ago

a roller skating rink offers a special rate for birthday parties. On the samr day, a party for 10 skaters cost $107 and a party

olga nikolaevna [1]

Answer:

$119

Step-by-step explanation:

Let

x -----> the number of skaters

y -----> the cost for birthday parties

we have the points

(10,107) and (15,137)

step 1

Find the slope of the linear equation

The formula to calculate the slope between two points is equal to

$m=\frac{y2-y1}{x2-x1}$

substitute the values

$m=\frac{137-107}{15-10}$

$m=\frac{30}{5}=6\ \frac{\$}{skater}$

step 2

Find the equation of the line in point slope form

$y-y1=m(x-x1)$

we have

$m=6\\point\ (10,107)$

substitute

$y-107=6(x-10)$

step 3

Convert to slope intercept form

$y-107=6x-60$

$y=6x-60+107$

$y=6x+47$

step 4

How much would a party for 12 skaters cost?

For x=12 skaters

substitute the value of x in the equation and solve for y

$y=6(12)+47$

$y=\$119$

4 0

3 years ago

A water balloon is tossed into the air with an upward velocity of 25ft/s. Its height H(t) in ft after t seconds is given by the

FinnZ [79.3K]

19. It notes or hints to using the quadratic formula because the equation can not be solved by factoring alone. Thus you must use the quadratic formula.
A=-16 B=25 C=3
It is so hard to type a normal equation let alone one of the quadratic formula so I will just attach a picture instead.
However you will end up getting two roots/zeros/x-intercepts of -0.11 and 1.67.
However since it is an application question asking for answers only in the first quadrant you must choose the positive x-intercept.
Therefore the water balloon will land at 1.67 seconds.

20. This question is very simple as it asks you to find a height at a given time. You simply put the given time (1second) into the equation and get your answer.
h=-16(1)^2+25(1)+3
h=12

Also don't mind my little scribble there. :)

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3 years ago