Calculate the amount and the compound interest on ₹ 8000 in $2\dfrac{1}{2}$ years at 15% per annum.

For first year :

P = ₹ 8000

T = 1 year

R = 15%

I = $\dfrac{P \times R \times T}{100}$

$= \dfrac{8000 \times 15 \times 1}{100}$ = ₹ 1200.

Amount = P + I = ₹ 8000 + ₹ 1200 = ₹ 9200.

For second year :

P = ₹ 9200

T = 1 year

R = 15%

I = $\dfrac{P \times R \times T}{100}$

$= \dfrac{9200 \times 15 \times 1}{100}$ = ₹ 1380.

Amount = P + I = ₹ 9200 + ₹ 1380 = ₹ 10580.

For next half year :

P = ₹ 10580

T = $\dfrac{1}{2}$ year

R = 15%

I = $\dfrac{P \times R \times T}{100}$

$= \dfrac{10580 \times 15 \times \dfrac{1}{2}}{100}$ = ₹ 793.50

Amount = P + I = ₹ 10580 + ₹ 793.50 = ₹ 11373.50

Compound interest = Final amount - Initial principal

= ₹ 11373.50 - ₹ 8000 = ₹ 3373.50

Hence, amount = ₹ 11373.50 and compound interest = ₹ 3373.50