To find : Compound interest accumulated after 1 year.
P = 2500, r = 0.053 (5.3%), n = 12 , and t = 1 (given)
Using monthly compound interest formula,
CI = P(1 + (r/n))nt - P
Put the values given
CI = 2500{1 + (0.053/12)}12 - 2500
CI = 2500{(12 + 0.053 )/12}12 - 2500
= 2500(12.053/12)12 - 2500
= 2500(1.0044)12 - 2500
= 2500(1.0633) - 2500
= 2658.25 - 2500
= 158.25
So, the compound interest after 1 year will be Rs 158.25 .
To find : Interest rate (r) = ?
P = 900, n = 12, and t = 1, Amount = 3600 (given)
Using formula,
CI = Amount - Principal
Put the values,
CI = 3600 - 900 = 2700
Using monthly compound interest formula,
CI = P(1 + (r/12) )12t - P
Put the given values ,
2700 = 900 {1 + (r/12)}12×1 - 900
2700 = 900 {1 + (r/12)}12
2700 + 900 = 900 {1 + (r/12)}12
3600/900 = {1 + (r/1200)}12
Reduce the RHS by power of 12
(41/12) x 1200 = 1200 + r
1.12246 x 1200 = 1200 + r
1346.954 = 1200 + r
r = 1346.954 - 1200
r = 146.95%
Therefore the rate of interest is 146.95 %
To find : Compound interest accumulated after 2 year.
P = 3500, r = 0.03 (3%), n = 12 , and t = 2 (given)
Using monthly compound interest formula,
CI = P(1 + (r/n))nt - P
Put the values given
CI = 3500 {1 + (0.03/12)}12x2 - 3500
CI = 3500 {(12 + 0.03 )/12}24 - 3500
= 3500(12.03/12)24 - 3500
= 3500(1.0025)24 - 3500
= 3500(1.061757) - 3500
= 3716.125 - 3500
= 216.125
So, the compound interest after 2 year will be Rs 216.125.
To find : Compound interest accumulated after 3 year.
P = 5000, r = 0.05(5%), n = 12, and t = 3 (given)
Using monthly compound interest formula,
CI = P(1 + (r/n))nt - P
Put the values given
CI = 5000{1 + (0.05/12)}12x3 - 5000
CI = 5000{(12 + 0.05 )/12}36 - 5000
= 5000 (12.05/12)36 - 5000
= 5000 (1.00416)36 - 5000
= 5000 ( 1.1611946) - 5000
= 5805.973 - 5000
= 805.973
So, the compound interest after 3 year will be Rs 805.973.
To find : Compound interest accumulated after 2 year.
P = 1758, r = 0.04 (4 %), n = 12, and t = 2 (given)
Using monthly compound interest formula,
CI = P(1 + (r/n))nt - P
Put the values given
CI = 1758 {1 + (0.04/12)}12x2 - 1758
CI = 1758 {(12 + 0.04)/12}24 - 1758
= 1758(12.04/12)24 - 1758
= 1758(1.0033)24 - 1758
= 1758(1.0822796) - 1758
= 1902.647 - 1758
= 144.647
So, the compound interest after 3 year will be Rs 144.647.
To find : Compound interest accumulated after 5 year.
P = 2000 , r = 0.07 (7%), n = 12 , and t = 5 (given)
Using monthly compound interest formula,
CI = P(1 + (r/n))nt - P
Put the values given
CI = 2000 {1 + (0.07/12)}12x5 - 2000
CI = 2000{(12 + 0.07)/12}60 - 2000
= 2000(12.07/12)60 - 2000
= 2000(1.00583)60 - 2000
= 2000(1.417625) - 2000
= 2835.250 - 2000
= 835.250
So, the compound interest after 3 year will be Rs 835.250.