16% of students scored higher than 80 on a recent normally distributed exam the standard deviation is 10 what is the mean

Mathematics

1 answer:

Crazy boy [7]3 years ago

7 0

Answer:

70.06

Mean score = 70

Step-by-step explanation:

16% of students scored higher than 80 on a recent normally distributed exam the standard deviation is 10 what is the mean

For a normal distribution :

Zscore = (x - mean) / standard deviation

x = score

P(Z > 80) = 16% = 0.16 ; corresponding Zscore = 0.994 (Z probability calculator)

Therefore ;

0.994 = (80 - mean) / 10

0.994 * 10 = 80 - mean

9.94 = 80 - mean

Mean = 80 - 9.94

Mean = 70.06

Hence, the mean score = 70.06 = 70

You might be interested in

Can someone answer my questions please ._.

tekilochka [14]

Answer:

wheres the question?

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

What are the approximate solutions of 4x2 + 3 = −12x to the nearest hundredth?

Gwar [14]

First
$4x^{2} + 12x + 3 = 0$
determine if this equation were factorable, it's not for this one
so I use quadratic formula, try to search the formula online

$x1 = \frac{-12 + \sqrt{(12)^{2} - 4*4*3} } {2*4} = \frac{-12 + 4\sqrt{6} }{8} = \frac{4(-3 + \sqrt{6}) }{8} = \frac{-3 + \sqrt{6}}{2} = - 0.28$
$x2 = \frac{-12 - \sqrt{(12)^{2} - 4*4*3} } {2*4} = \frac{-12 - 4\sqrt{6} }{8} = \frac{4(-3 - \sqrt{6}) }{8} = \frac{-3 - \sqrt{6}}{2} = - 2.72$

<span>x ≈ −2.72 and x ≈ −0.28 is the solution</span>

3 0

4 years ago

Write 62° 21' 47"' as a decimal to the nearest thousandth.

Taya2010 [7]

Answer:

i dont get the question

Step-by-step explanation:

idk

4 0

4 years ago

Read 2 more answers

I need help plz and thank you