Answer:
C = 21.55*5 +(0,75*21.55) = 123.9125
Step-by-step explanation:
So because you have the average rainfall in a year, then for a 5 year period, you just multiply that number by 5 (21.55*5 = 107.75 inches).
Then because you want the rainfall for 5.75 years and you've just calculated it for 5 years as shown above, you still need to do it for the remaining 0.75 years (5.75 -5 = 0.75).
So you just multiply 0.75*21.55 = 16.1625 inches. The add the calculated inches for 5 years with the inches for 0.75 years.
