Given: Total sum = Rs. 6100 In Scheme A, Compound interest Principal = P R = 10% per annum for 2 years In Scheme B, Simple interest Principal = 6100 - P R = 10% per annum for 4 years CI = SI Concept Used: S.I =
PRT
100
C.I = P [1+(
R
100
)T - 1] P = Principal R = Rate of Interest T = Time Calculation: According to the question, we get CI = SI ⇒ P [1+(
R
100
)T - 1] =
PRT
100
⇒ P[1+
10
100
2 - 1] =
[(6100−P)4×10]
100
⇒ P ×
21
100
=
[(6100−P)×4×10]
100
⇒ 21P = 6100 × 40 - 40P ⇒ 61P = 6100 × 40 ⇒ P = 4000 ∴ The amount invested in Scheme A is Rs. 4000.