Question

1 At what per cent per annum simple interest will a
sum of money double itself in one year?​

Answer 1

Solution :-

➥ Let Principal be = P

➥ Time = 10 years

➥ Rate = ?

➥ Amount = 2p

$\bf{{ = > SI = \frac{P × Rate × Time}{100} }}$

$\bf{{=>SI = A-P}}$

$\bf{{ = > 2p - p = \frac{P×R×10}{100} }}$

$\bf{{ = > P = \frac{P \: × \: R \: × \: \cancel{{10}}}{10 \: \times \: \cancel {{10}}} }}$

$\bf{{ = > 10 = \frac{\cancel{{P}}×R}{ \cancel{{P}} }}}$

$\bf{{ => 10 = R}}$

$\bf{{ = > Rate = 10\%}}$

Hope you understand this answer mate ッ