The answer is X= 25
You just have to divide 125 by 5
The insurance period must be chosen so that the probability of a microchip failure within that period is 4%. Reference to a standard normal distribution table shows that the z-score for a cumulative probability of 4% is -1.75.
Let the insurance period be X months:
-1.75 = (X - 93)/3.8
-6.65 = X - 93
X = 83.35 months.
The answer is 83.35 months.
It might be 0.133928571.....? I am unsure though. Sorry if this doesn't help
A = 30,000 - 2000m where A=altitude and m = number of minutes
After 5 minutes A ( altitude) = 30,000 - 2000(5) = 20,000 feet