IMO D.

Let her monthly take home salary = 100rs.
Let her savings /month = x
Total Saving at the end of year = 12x

Now, Money she didnt save /month = 100-x

12x = 3( 100-X)
x = 20
So, She saved 20 rs/month which is equivalent to 1/5 of her monthly take home. So IMO D = 1/5

OA Pls

OA D tnx

Assign variables:

p = take home pay per month
s = fraction saved per month

So savings at the end of the year = 12*s = 12s

p-s = money not saved per month.
Annual savings = 3 times money not saved per month - this can be expressed as:
12s = 3(p-s)
12s = 3p - 3s
15s = 3p
s = 3/15(p)
s = 1/5 (p)

So the savings are one fifth of the pay. Answer D.

Key with these questions is to assign variables to the unknowns. Using the information provided generate equations, and then solve for the unknown.

Hope this helps.