Answer:
B. 4,1
Step-by-step explanation:
x = number of hours
want to find probability (P) x >= 13
x is N(14,1) transform to N(0,1) using z = (x - mean) / standard deviation so can look up probability using standard normal probability table.
P(x >= 13) = P( z > (13 - 14)/1) = P(z > -1) = 1 - P(z < -1) = 1 - 0.1587 = 0.8413
To convert that to percentage, multiply 100, to get 84.13%
30 = 6 x 5
6 = 3 x 2
8 = 4 x 2
4 x 2 + 3 x 2 + 6 x 5 = 44
