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If 7000 dollars is invested in a bank account at an interest rate of 4 per cent per year,

a. Find the amount in the bank after 9 years if interest is compounded annually
b. Find the amount in the bank after 9 years if interest is compounded quaterly
c. Find the amount in the bank after 9 years if interest is compounded monthly
d. Finally, find the amount in the bank after 9 years if interest is compounded continuously

User Dhiraj Ray
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Final answer:

a. After 9 years with annual compounding, the amount in the bank will be approximately $9858.25. b. After 9 years with quarterly compounding, the amount in the bank will be approximately $10060.41. c. After 9 years with monthly compounding, the amount in the bank will be approximately $10071.88. d. After 9 years with continuous compounding, the amount in the bank will be approximately $10084.72.

Step-by-step explanation:

a. To find the amount in the bank after 9 years with annual compounding, we can use the formula:

A = P(1 + r/n)^(nt)

where A is the amount in the bank, P is the initial investment, r is the interest rate, n is the number of times interest is compounded per year, and t is the number of years.

Using the given values, we have:

A = 7000(1 + 0.04/1)^(1*9) = 7000(1.04)^9 ≈ $9858.25

b. To find the amount in the bank after 9 years with quarterly compounding, we use the same formula with n = 4:

A = 7000(1 + 0.04/4)^(4*9) = 7000(1.01)^36 ≈ $10060.41

c. To find the amount in the bank after 9 years with monthly compounding, we use the same formula with n = 12:

A = 7000(1 + 0.04/12)^(12*9) = 7000(1.003333)^108 ≈ $10071.88

d. To find the amount in the bank after 9 years with continuous compounding, we use the formula:

A = Pe^(rt)

where e is the base of the natural logarithm. Using the given values, we have:

A = 7000e^(0.04*9) ≈ $10084.72

User Obs
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