Q10. Mario invested Rs.8,000 in a plan. She would be paid interest at 5% per annum calculated
annually. Find:
1) the amount credited against his name at the end of third year.
ii) amount at the end of 1 and a half years if compounded half yearly.
Answers
Step-by-step explanation:
(i) Here, Principal (P) = Rs. 8000, Rate of Interest (R) = 5%, Time (n) = 2 years.
Amount (A) = P\left(1+\frac{R}{100}\right)^nP(1+
100
R
)
n
= 8000\left(1+\frac{5}{100}\right)^28000(1+
100
5
)
2
= 8000\left(1+\frac{1}{20}\right)^28000(1+
20
1
)
2
= 8000\left(\frac{21}{20}\right)^28000(
20
21
)
2
= 8000\times\frac{21}{20}\times\frac{21}{20}8000×
20
21
×
20
21
= Rs. 8820
(ii) Here, Principal (P) = Rs. 8000, Rate of interest (R) = 5%, Time (n) = 3 years.
Amount (A) = P\left(1+\frac{R}{100}\right)^nP(1+
100
R
)
n
= 8000\left(1+\frac{5}{100}\right)^38000(1+
100
5
)
3
= 8000\left(1+\frac{1}{20}\right)^38000(1+
20
1
)
3
= 8000\left(\frac{21}{20}\right)^38000(
20
21
)
3
= 8000\times\frac{21}{20}\times\frac{21}{20}\times\frac{21}{20}8000×
20
21
×
20
21
×
20
21
= Rs. 9,261
Interest for 3rd year = A - P
= Rs. 9,261 – Rs. 8,820 = Rs. 441
Answer:
1)=16
2)40
I hope it is helpful