Answer:
I BELIEVE ITS C
Step-by-step explanation:
We have the formula A = (h x b) / 2, where A is the area of the triangle, h is the height of the triangle, b is the base of the triangle;
So, 32 =(8 x b) / 2;
Then, 64 = 8 x b;
b = 64 ÷ 8;
b = 8 inches;
Answer:
Hi your question is incomplete attached below is the complete question
answer : p ( X < 725 ) = 0.0116
Step-by-step explanation:
Given data:
Average life of bulbs (μ ) = 750 hours
standard deviation (б ) = 55 hours
n ( sample size ) = 25
X = 725
<u>Probability that the mean life of a random sample of 25 bulbs will be less than725 hours </u>
p ( X < 725 ) = p (( X - μ )/ б √n < 725 - 750 / 55√25 )
= P ( Z > - 2.27 )
Hence P ( X < 725 ) = 0.0116 ( using Z-table )
Answer:
not positive but i would say 48
Step-by-step explanation:
Answer:
Step-by-step explanation:
We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean
For the null hypothesis,
µ = 12
For the alternative hypothesis,
µ < 12
Since the population standard deviation is given, z score would be determined from the normal distribution table. The formula is
z = (x - µ)/(σ/√n)
Where
x = sample mean
µ = population mean
σ = population standard deviation
n = number of samples
From the information given,
µ = 12 minutes
x = 8 minutes
σ = 12 minutes
n = 36
z = (8 - 12)/(12/√36) = - 4/2 = - 2
Test statistic = - 2
