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Each of the questions given below consists of two statements numbered I and II given below it. Please read the questions carefully and decide whether the data provided in the statement(s) is / are sufficient to answer the given question.

1)

What was the rate of interest on a sum of money ?

I. The sum fetched a total of Rs. 2522 as compound interest at the end of 3 years.

II. The difference between the simple interest and the compound interest at the end of 2 years at the same rate was Rs. 40


A) I alone sufficient while II alone not sufficient to answer

B) II alone sufficient while I alone not sufficient to answer

C) Either I or II alone sufficient to answer

D) Both I and II are not sufficient to answer

E) Both I and II are necessary to answer

Answer:

Option E

Explanation:

I gives : C.I for 3 years = Rs. 2522.

II gives : (C.I)(S.I) for 2 years at same rate is Rs. 40.

[(1+R100)31] =2522 ---(i)

[(1+R100)21] P×R×2100 =40 ---(ii)

On dividing (i) by (ii) we get :

(1+R100)31(1+R100)21R50 =252240

R31000000+3R100+3R210000R210000 =126120

R100 +300R =120120 R2 6005R +30000 =0

R26000R 5R+30000 =0

R(R6000) 5(R6000) =0

(R5)(R6000) =0

R=5

Both I and II are needed to get R.

Correct answer is (E).