Question

at what rate percent per annum will a sum of 6250rs amount to 7840rs in 2 years compounded annually​

Answer 1

Answer:

which class chapter is this

Answer 2

Given :

Amount = 7840

Principal = 6250

Time = 2 years

To find :

Rate percent

Solution :

Finding Rate Percentage -

$= > Amount \: = principal(1 + \dfrac{r}{100} )^{2}$

$= > 7840 = 6250(1 + \frac{r}{100} )^{2}$

$= > \dfrac{7840}{6250} = (1 + \frac{r}{100} )^{2}$

$= > \dfrac{784}{625} = (1 + \frac{r}{100} )^{2}$

$= > ( \dfrac{28}{25} )^{2} = (1 + \frac{r}{100 } )^{2}$

$= > \dfrac{28}{25} = 1 + \dfrac{r}{100}$

$= > \dfrac{100 + r}{100} = \dfrac{28}{25}$

$= > 25(100 + r) = 28 \times 100$

$= > 2500 + 25r = 2800$

$= > 25r = 2800 - 2500$

$= > 25r = 300$

$= > r = \dfrac{300}{25} = 12\%$

Hence, Rate = 12%