Question

in what time will the simple interest on rs 400 at 10% per annum be the same as the simple interest on rs 1000 for four years at 4% per annum

Answer 1

prt/100=prt/100
400*10*t/100=1000*4*4/100
t=16000/4000
t=4years....ans....

Answer 2

Answer:

After 4 years.

Step-by-step explanation:

Let, after t years the simple interest on rs 400 at 10% per annum be the same as the simple interest on rs 1000 for four years at 4% per annum,

Since, The simple interest is,

$S.I.=\frac{P\times r\times t}{100}$

Where, P is the principal amount,

r is the annual rate of interest,

t is the time ( In years ),

Thus, the simple interest on rs 400 at 10% per annum for t years,

$=\frac{400\times 10\times t}{100}$

$=\frac{4000t}{100}=40t$

While, the simple interest on rs  1000 for four years at 4% per annum

$=\frac{1000\times 4\times 4}{100}=\frac{16000}{100}=160$

Hence,

40 t = 160

⇒ t = 4 years