Answer: 0.0031
Step-by-step explanation:
Binomial distribution formula :-
, where P(x) is the probability of x successes in the n independent trials of the experiment and p is the probability of success.
Given : A binomial probability experiment is conducted with the given parameters.

Now, 

Hence, 
Answer:
10
Step-by-step explanation:
45 hours.
80 - 70= 10, and 450/10 is 45.
to justify, you can do 70x45= 3,150, and 80x45= (3,600 - 3,150= 450)
I do believe the answer is 52, sorry if i’m incorrect