Question

how many years will be required to double the principal amount of rs. 5000/- by simple interest at the rate of 4 p.c.p.a. ​

Answer 1

$Given \: Principal (P) = Rs \: 5000 ,\\Amount(A) = 2P\\ = 2\times 5000\\= Rs\:10000$

$Rate \: of \: Interest (R) = 4 \% \: per \:annum$

$Let \: Time = T \: years$

$\boxed { \pink { Simple \: interest (S.I) = A - P }}$

$= Rs \: 10000 - Rs \: 5000 \\= Rs \: 5000$

$\boxed { \orange { T = \frac{ 100\times S.I }{PR} }}$

$= \frac{ 100\times 5000}{5000 \times 4} \\= \frac{100}{4} \\= 25\%$

Therefore.,

$\red { Required \: time } \green { = 25\% }$

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