Question

HELP ASAP FOR BRAINLIEST: The time required to finish a test is normally distributed with a mean of 60 minutes and a standard deviation of 10 minutes. What is the probability that a student will finish the test in less than 70 minutes?
Show work please!

Answer 1

Answer:

Step-by-step explanation:

Since the time required to finish the test is normally distributed, we would apply the formula for normal distribution which is expressed as

z = (x - µ)/σ

Where

x = time taken to finish test.

µ = mean time

σ = standard deviation

From the information given,

µ = 60 minutes

σ = 10 minutes

We want to find the probability that a student will finish the test in less than 70 minutes. It is expressed as

P(x ≤ 70)

For x = 70,

z = (70 - 60)/10 = 1

Looking at the normal distribution table, the probability corresponding to the z score is 0.8413

Therefore,

P(x ≤ 70) = 0.8413

Answer 2

Answer:

About 84.13%

Step-by-step explanation:

Using gaussian distribution function

f(t)=$\frac{1}{\sqrt{2\pi\sigma^2 } }e-(t-t_a_v_g)^2/2\sigma^2$

T- 60

sigma- 10

we then consider the range between [0,70)

=.841345 or 84.13%