<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: 11/30
Step-by-step explanation:
11 girls out of 30 kids. 11/30 cannot be simplified.
Answer: 35.6 (choice A)
To get this answer, add up the values: 39+42+27+45+25 = 178
Next, divide that result by 5 because there are 5 scores added up in the previous step. Doing this division gets us to: 178/5 = 35.6
Answer:
16/33
Step-by-step explanation:
The probability that the first ball is red and the second ball is black is:
8/12 × 4/11 = 8/33
The probability that the first ball is black and the second ball is red is:
4/12 × 8/11 = 8/33
So the total probability of drawing one ball of each color is 8/33 + 8/33 = 16/33.
Hi,
In a triangle, all angles must add up to 180*.
73 + 40 = 113
180 - 113 = 67
Thus, the measure of Z is equal to 67