Question

The difference between S.I. and C.I. on a sum of money for 2 years
is 15. The S.I. on the same sum for 4 years is 1,200. Find the sum
and rate of interest.​

Answer 1

Answer:

Compound interest = Amount − Principal

C.I.=P(1+

100

R

)

n

−P=P[[1+

100

5

]

4

−1]

C.I.=0.2155P

Simple interest, S.I. =

100

PNR

S.I.=

100

P×5×4

S.I.=0.2P

Now C.I. − S.I. =15

⇒0.2155P−0.2P=15

⇒P=

0.0155

15

⇒P= Rs. 967.74

Answer 2

Step-by-step explanation:

answer is 15

Compound interest = Amount - p

C.l = p (1+100)

Rn - p=p[[1+1005]4-1]

C.l= 0.2155p

simple interest, S.l =100 PNR

S.l =100

p×5×4

S.l = 0.25

Now C.l - 5.1 =15

=0.2155p-0. 2p =15

= p= 0.0155

15

= P = Rs. 967.74