**Problem 1:** When a certain principal is invested at 16.66% compound interest instead of 12.5% per annum for 2 years the interest is 550 more. Find the principal?

Solution:

12.5% ——–>——–>64

16.66%——–>——–>36

LCM Of 64 and 36 is 576 is principal

72+72+9=153 96+96+16=208

208-153=55

55———->550

576——–>?

**Problem 2:** Raju took Rs.38400 from Rama at 10% rate of SI and give it to Surya who gives 12.5% rate of C.I compounded annually. If Raju gives the money to Surya for 3 years and returns to Rama immediately. Find the profit of Raju?

Solution:

S.I=

4800*3=14400

600*3=1800

14400+1800+75=16275

16275-11520=4755

**Problem 3:** A man invested a sum of money in scheme A, at the rate of 15% per annum for S.I, at the end of two years the amount received by him is invested in scheme B at 20% per annum for C.I. If the interest received by him from scheme B at the end of the second year is RS. 2860, then find the sum invested by a man in the beginning?

Solution:

Scheme B=20% C.I

20+20+%

Scheme A=15% S.I

Assume principal is 100

%

44%——–>2860

100%——–>?

**Problem 4:** A and B have an amount in 2:3 if A buy a car from his money whose price is depreciated by 10% whereas B invested that money in the bank which gives C.I at the rate of 20% per annum. Find the total percentage change in the total amount?

Solution:

10%=– ——> Depreciates —–>

20%= ———> Increases ——->

A : B

2 : 3

:

1 : 2

% change