Question

If 360 becomes rupees 435.60 in three years then what will be a sum of rupees 700 in 7 years?

Answer 1

Given:-

•Principal is given = 360 rupees.

•Amount is given = 435.60 rupees.

•Time is given= 3years

•Second Principal= 700rupees

• Second Time = 7years

To Find:-

• Simple Interest = ?

•Rate of interest =?

•Amount = ?

Solution:-

Given,

• P = 360rupees
• A = 435.60 rupees

As we know,

$\: \: \sf \: simple \: interest = amount - principal$

Now substitute the values

$\: \: \sf \: simple \: interest = 435.60 - 360 \\ \\ \: \: \sf \: simple \: interest = 75.60 \: rupees$

Given,

• P = 360 rupees
• S.I = 75.60rupees
• T = 3years

As we know,

$\: \: \sf \: rate = \frac{principal \times 100}{simple \: interest \times time}$

Now substitute the values

$\: \: \sf \: rate = \frac{75.60 \times 100}{360 \times 3} \\ \\ \: \: \sf \: rate = \frac{7560 \times 100}{360 \times 3 \times 100} \\ \\ \: \: \sf \: rate = 7 \: percent$

Hence,rate of interest is 7%.

Now,

• P = 700rupees
• T = 7years
• R = 7%

As we know,

$\: \: \sf \: amount = \frac{principal}{100} \times ({100 + rt})$

Now substitute the values,

$\: \: \sf \: amount = \frac{700}{100} \times (100 + 7 \times 7) \\ \\ \: \: \sf \: amount = \frac{700}{100} \times 149 \\ \\ \: \: \sf \: amount = 1043 \: rupees$

Hence,amount is 1043 rupees.

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