On a certain sum of money, the simple interest for 2 years

On a certain sum of money, the simple interest for 2 years is Rs. 350 at the rate of 4% per annum. It was invested at compound interest at the same rate for the same duration as before, how much more interest would be earned?

Given that , S.I. = Rs. 350 , Time = 2 years , Rate = 4%
As we know that ,

Principal =	S.I. × 100
	Time × Rate

Principal =	350 × 100	= Rs. 4375
	2 × 4

C.I. = P			1 +	R		^T	− 1
				100

C.I. = 4375			1 +	4		²	− 1
				100

C.I. = 4375			1 +	1		²	− 1
				25

C.I. = 4375			26		²	− 1
			25

C.I. = 4375		676	− 1
		625

C.I. =	4375 × 51	= Rs. 357
	625

Required difference = C.I. - S.I.
∴ Required difference = Rs. (357 – 350) = Rs. 7