THE FARMER INVESTED MONEY WITH COMPOUND INTEREST (CAMBRIDGE PAST PAPER)
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(i) Calculate the total value of his investment after the 3 years.
(ii) The farmer wants to spend his investment on buying goats.
Goats cost $126 each.
Work out the maximum number of goats he can buy and how much money is left over.
Mathematics Cambridge IGCSE Test (0580 m16 qp 32)
Answer:i) The formula of Compound Interest is
A=P (1+R/100)^T
The Amount A is the total of money with its interest, after T years.
P = $3750
After first year = $3750 + 4% x $3750 = $3900
After second year = $3900 + 4% x $3900 = $4056
After third year = $4056 + 4% x $4056 = $4218.24
Or simply use the formula
A=$3750(1+4/100)^3
A=$4218.24
(ii) Number of goats will be calculated as
=$4218.24/126
=33.49
Exact the maximum number of goats he can buy are 33 goats.
The remaining money after he bought goats is 60.24