Question

what sum will yield an interest of rs. 277.50 for 3 years at 12% per annum??

Answer 1

Given,

            S.I. = 277.50

            T =3 years

            R = 12 % p.a.

SI = PRT /100

277.50   = P*12*3/100

277.50*100=P*12*3

27750 /12*3 = P

P = 6937.5

Therefore, the principal amount is 6937.5

Answer 2

$\huge\red{Answer\: is}$

Sum = let P
SI = ₹ 277.50
T = 3 years
R = 12% p.a

we know
$p = \frac{277.50 \times 100}{3 \times 12} \\ p = \frac{27750}{36} \\ p = 770.83$
Sum = ₹ 770.83

Hope it helps you