(-7,3) here is the answer, easy one
<span>4(9n-9)
= 4*9n -4*9 (distributive property)
= 36n -36
The correct answer is c. </span>36n -36~
Answer:
the probability that the sample variance exceeds 3.10 is 0.02020 ( 2,02%)
Step-by-step explanation:
since the variance S² of the batch follows a normal distribution , then for a sample n of 20 distributions , then the random variable Z:
Z= S²*(n-1)/σ²
follows a χ² ( chi-squared) distribution with (n-1) degrees of freedom
since
S² > 3.10 , σ²= 1.75 , n= 20
thus
Z > 33.65
then from χ² distribution tables:
P(Z > 33.65) = 0.02020
therefore the probability that the sample variance exceeds 3.10 is 0.02020 ( 2,02%)
C) They solve the same number of problems per minute
172.5 Divided by 2
115 divided by 2
= 57.5
You would take d times t seconds and find the answer