Question

The compound interest on $Rs.64,000$ for $3$ years, compounded annually at $7.5$% per annum is

• A. $Rs.14,400$
• B. $Rs.15,705$
• C. $Rs.15,507$
• D. $Rs.15,075$

Answer 1

Answer: (C)

$Rs.15,507$

$Principal=64000$
$Rate=7.5\%p.a$
$Time=3years$
$\text{Where r is the rate and t is the time.}$
$CI=64000(1+7.5/100{)}^3-64000$
$=64000(1+75/1000{)}^3-64000$
$=64000(1+3/40{)}^3-64000$
$=64000\times (43/40{)}^3-64000$
$=64000\times (43/40\times 43/40\times 43/40)-64000$
$=(43\times 43\times 43)-64000$
$=79507-64000$
$=15507$
$\text{Hence CI will be 15507 rupees}$