Answer:
14
Step-by-step explanation:
6 x 10 = 60
60 - 5 = 55
5 x 10 = 50
50 - 9 = 41
55 - 41 = 14
Area of rectangle b=1/2 area of rectangle a=40/2=20 cm²
Length=8 cm
Width of rectangle b=20/8 =2.5 cm
We have the mean, μ = 20 and the standard deviation, σ = 4
X ≈ N(20, 4²)
We want P(X<15)
Standardising gives
P(X<15) = P(Z<

)
P(X<15) = P(Z< -1.25) ⇒ When the value of the z-score is negative, we will read the value of z<1.25 on the z-table then subtract the answer from 1
P(X<15) = 1 - P(Z<1.25)
P(X<15) = 1 - 0.8944
P(X<15) = 0.1056
Hence, the probability that pizza takes less than 15 minutes to be delivered is 0.1056 = 10.56%