Question

19. There is an increase of 12% in the rainfall of a city in one year. If the rainfall this year is 39.2
cm, what was it a year ago ?​

Answer 1

Answer:

We know that the rainfall increases at a rate of 12% per year and the amount of rainfall this year is 39.2 cm.

Now suppose, last year's rainfall was X cm.

So, there was the amount of rainfall last year-

X×112% = 39.2

or, X×112/100 = 39.2

or, X = 39.2×100/112

or, X = 35

So, one year ago the amount of rainfall was 35 cm.