Question

11. Find the time in which a sum of money gets doubled at the interest rate of 8% per annum.plz don't give unnecessary answers.answer with explanation needed...​

Answer 1

GiveN :-

• Rate of interest = 8% per annum.

To finD :-

• The time in which principal (p) will be double at a rate of 8 % per annum.

SolutioN :-

$\sf{Let ,}$

$\sf{ \: \: \: \: \: \: Principal = ₹ P}$

$\sf{∴ \: \: \: \: \: \: Amount = ₹ \: 2P}$

Simple interest = Amount - Principal

= ₹ 2P - ₹ P

= ₹ P

By using the formula

$\underline{\boxed{\sf \: Time \: = \frac{100 \times S .I}{p \times r} }}$

$\sf{ \implies \: time \: = \frac{100 \times p}{ p\times 8} }$

$\sf{ \implies \: time \: = \frac{100}{8} \: years }$

$\sf{ \implies \:time = \frac{25}{3} \: years }$

$\sf{ \implies \: time \: = 12 \frac{1}{2} \: years}$

$\sf{ \implies \: time \: = 12 \: years \: + \: \frac{1}{2} years }$

$\sf{ \implies \:time \: = 12 \: years \: 6 \: months }$

Therefore , 12 years and 6 months is needed to get doubled a sum of money at a interest of 8% per annum.

Answer 2

$\sf{ \: I \: think \: 12 \: years \: and \: 6 \: months}$