Answer:
The answer is 4:8 which simplifies to 1:2
Step-by-step explanation:
There are 4 months that have 30 days
in a year, there are 12 months in total.
So there are 12-4 = 8 months with other than 30 days.
The ratio of the months with 30 days to the months with other than 30 days is
4:8 which simplifies to 1:2
It is 102.5. You made it kind of confusing at first by putting the divisor first in your question then putting your dividend, but I understand what you meant.
The standardized probability of a normally distributed data is given by
P(X < x) = P(z < (x - mean) / standard deviation)
P(X > x) = 1 - P(X < x)
P(X > 125) = 1 - P(X < 125) = 1 - P(z < (125 - 100) / 15) = 1 - P(z < 25/15) = 1 - P(z < 1.667) = 1 - 0.95221 = 0.04779 = 4.8%
Though it cannot be said to be usual, at the same time it is not unusual because 125 is above the first standard deviation of the mean but below the second standard deviation of the mean.
The third option would be the incorrect one