Question

find the principal when simple interest 200 time is 5 year and rate of interest is 10% p.a.

Answer 1

Answer:

f P denotes the principal ($), R denotes the rate (percentage p.a.) and T denotes time (years), then:-

S.I = (P × R × T)/100

R = (S.I × 100)/(P × T) 

P = (S.I × 100)/(R × T)

T = (S.I × 100)/(P × R)

If the denotes the amount, then A = P + S.I

Find the simple interest on:

(a) $ 900 for 3 years 4 months at 5% per annum. Find the amount also. 

Solution:

P = $ 900, 

R = 5% p.a. 

T = 3 years 4 months = 40/12 years = 10/3 years

Therefore, S.I = (P × R × T)/100 = (900 × 5 × 10)/(100 × 3) = $ 150 

Amount = P + S.I = $ 900 + $ 150 = $ 1050

(b) $ 1000 for 6 months at 4% per annum. Find the amount also. 

Solution:

P = $ 1000, 

R = 4% p.a. 

T = 6 months = 6/12 years 

S.I = (P × R × T)/100 = (1000 × 4 × 1)/(100 × 2) = $ 20

Therefore, A = P + I = $( 1000 + 20) = $ 1020

(c) $ 5000 for 146 days at 15¹/₂% per annum. 

Solution:

P = $ 5000, R = 151/2% p.a. T = 146 days

S.I = ( 5000 × 31 × 146)/(100 × 2 × 365) 

= $ 10 × 31 = $ 310