They helped be great together
Answer:
Radius:
17
or
Diameter
34
or
Circumference:
106.8
Unit:
centimeters
Step-by-step explanation:
<span>solution:
we have, mean =8.4 hrs, std. deviation = 1.8 hrs, sample size n = 40 , X = 8.9
Probability(X<8.9) = ?
we know that, Z = (X - mean)/(std. deviation/(sqrt. n)) = (8.9 - 8.4)/(1.8/(sqrt.40))
Z = 1.7568
from standard normal probabilities table, we have , P(Z<1.7568) = 0.9608
Hence, probability that the mean rebuild time is less than 8.9 hours is 0.9608</span>
Answer:
666
Step-by-step explanation:
From this question,
a = 1-99%
a = 1-0.99
a = 0.01
5% = z(0.05) = 2.58 when we check the standard normal table
Therefore we calculate n as:
n = (z/E)²*p*1-p
Z = 2.58
E = 0.05
P = 0.5
1-p = 0.5
(2.58/0.05)²x0.5x0.5
= 51.6²x0.5x0.5
= 665.64
Therefore n is approximately 666.