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.
Answer:
C. 16
Step-by-step explanation:
Consider the number as 'n' (for now)
3n - 9 = 69
3n = 69 + 9
3n = 78
n = 78/3
n = 26
Therefore, The number is 26
