# Ex 8.3, 4 - Chapter 8 Class 8 Comparing Quantities

Last updated at Nov. 12, 2018 by Teachoo

Last updated at Nov. 12, 2018 by Teachoo

Ex 8.3, 4 I borrowed Rs 12,000 from Jamshed at 6% per annum simple interest for 2 years. Had I borrowed this sum at 6% per annum compound interest, what extra amount would I have to pay?Simple Interest Principal (P) = 12,000 Rate (R) = 6% per Annum Time (t) = 2 years. Interest (I) = (π Γ π Γ π)/100 = (12000 Γ 6 Γ 2)/100 = 120 Γ 12 = 1440 Compound Interest Principal (P) = 12,000 Rate (R) = 6% per Annum Time (t) = 2 years. Amount (A) = (1+π /100)^π A = 12000 Γ (1+ 6/100)^2 = 12000 Γ ((100 + 6)/100)^2 Now Amount (A) = Principal + Interest = 12000 + 1440 = 13440 = 12000 Γ ((100 + 6)/100)^2 = 12000 Γ (106/100)^2 = 12000 Γ (106 Γ 106)/(100 Γ100) = 12000 Γ 11236/10000 = (12 Γ 11236)/10 = 134832/10 = 13483.2 β΄ Amount using Simple interest = Rs 13440 & Amount using Compound interest = Rs 13483.2 Extra Amount = Amount Using Compound interest β Amount using Simple Interest = 13483.2 β 13440 = 43.2 β΄ I have to Pay Rs 43.20 extra