Question

At what rate percent per annum will RS. 1000 triple itself in 5 years

Answer 1

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\tt{\therefore{Rate\%=40\%}}}$

$\orange{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

$\green{\underline \bold{Given :}} \\ \tt: \implies Principal(p) = 1000 \: rupees \\ \\ \tt: \implies Time(t) = 5 \: years \\ \\ \tt: \implies Amount = 3 \: time \:of \: principal \\ \\ \red{\underline \bold{To \: Find :}} \\ \tt: \implies Rate\% (r)= ?$

• According to given question :

$\bold{For \: amount : } \\ \tt: \implies Amount = 3 \: times \: of \: principal \\ \\ \tt: \implies Amount =3 \times 1000 \\ \\ \green{\tt: \implies Amount =3000 \: rupees} \\ \\ \bold{For \: simple \: interest : } \\ \tt: \implies A = p + S.I\\ \\ \tt: \implies A - p = S.I \\ \\ \tt: \implies 3000 - 1000 = S.I\\ \\ \green{\tt: \implies S.I= 2000 \: rupees} \\ \\ \bold{As \: we \: know \: that} \\ \tt: \implies S.I = \frac{p \times r \times t}{100} \\ \\ \tt: \implies 2000 = \frac{1000 \times r \times 5 }{100} \\ \\ \tt: \implies 2000 \times 100 = 5000 \times r \\ \\ \tt: \implies r = \frac{200000}{5000} \\ \\ \green{\tt: \implies r = 40\%}$

Answer 2

$</p><p>\huge{\tt{\pink{Hello!!! }}}$

$</p><p>\tt{\red{Given \: - }}$

$\tt{ \orange{The \: above \: sum \: is \: in \: SI}}$

• Principle = Rs . 1000

• Time = 5 years.

• Amount = Rs. 5000

• Let the rate be r% per annum.

Therefore ,

$\tt{ \red{amount \: = 5 \: \times \: principal \: }}$

$</p><p>\tt{\blue{\ implies{A=p+S.I}}}$

From this we get S.I = Rs. 2000.

By the formula of SI ,

$</p><p>\tt{\orange{\dfrac{=>PTR}{100} = 2000 }}$

By substituting The required values we get r = 40%