Question

find the rate of interest at which a sum of money will double itself in 2 years if the interest is compounded annually explain in briefly

Answer 1

let the principal be x

simple interest will also be x

because the money doubles itself

amount will be 2x

amount = principal(100+rate/100)

2x = x(100+r/100)

2x/x = (100+r/100)

2 = 100+r/+100

$cross multiply$

200 = 100+ r

200-100 = r

100 = r