10. 120 days to months
a. 2mos.
b.3mos
C.4 mos
D. 5 mos

C. 4 months

Step-by-step explanation:

In order to find what is the equivalent number of months in 120 days, we can apply the following methods:  

Since there are 30 days in one month, then we can establish the following proportion statement in colon form:

30 days: 1 month = 120 days : x months

The expression of proportion in colon form, (a : b = c : d):

We could also establish the proportion statement in fraction form (ratio):

Then, use the Cross-product property, which involves the multiplication of extremes and the means:

30 days ×  x months = 1 month × 120 days

30x = 120

Then, divide both sides by 30 to solve for the value of x:

x = 4

Therefore, there are 4 months in 120 days, making Option C as the correct answer.