Question

A certain sum of money doubles itself in 12 years. in how many years will it treble itself by simple interest

Answer 1

↑ Here is your answer ↓
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Let the amount of money be 'x'

It will double in 12 months,

$2x = 12$

$x = 6$

Now to find when it triples itself!

$3x = 6*3$

$3x = 18$

Answer 2

Heya

Let the principal amount be 100

In 12 years, it becomes 200

Interest = 200-100=100

Interest = PTR/100

100 = 100×12×R/100

R = 100/12%

After T years, it becomes 300

Interest = 300-100=200

200 = (100 × T × 100/12 )/100

T = 200×12/100

T = 24

In 24 years, the amount triples itself

Hope it helps! ^_^