Answer:
7x
Step-by-step explanation:
9x-2x=7x
Answer:
5 jumps
Step-by-step explanation:
Personally I would write it out, although there surely is a formula for it.
3 fall to 2 - 5 fall to 4 - 7 fall to 6 - 10 fall to 9 - 12.
This makes 5 jumps, since once he is out he won't fall back in.
Answer:
Answer is C
Step-by-step explanation:
Hope it helps!
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%)