A certain sum of money yields ₹ 1261 as compound interest

A certain sum of money yields ₹ 1261 as compound interest for 3 years at 5% per annum. The sum is

Let the principal be ₹ p.
Here , CI = ₹ 1261 , R = 5%, T = 3 years
Using the given formula ,

Now, C.I. = P			1 +	R		^T	− 1
				100

⇒ 1261 = p			1 +	5		³	− 1
				100

⇒ 1261 = p		9261	− 1
		8000

⇒ 1261 = p		9261 − 8000
		8000

⇒ 1261 =	1261p
	8000

⇒ p =	1261 × 8000	= ₹ 8000
	1261