Answer:
Step-by-step explanation:
The growth rate of the coin is exponential. We would apply the formula for exponential growth which is expressed as
y = ab^x
y = b(1 + r)^ t
Where
y represents the value of the coin after x months.
x represents the number of months.
a represents the initial value of the coin.
b represents rate of growth.
From the information given,
a = 243
b = 1 + 15/100 = 1 + 0.15 = 1.15
Therefore, the exponential expression to determine the number of months, x it will take for the coin to attain a certain value, y is expressed as
y = 243(1.15)^x
If y = 1000, it means that
1000 = 243(1.15)^x
1000/243 = 1.15^x
4.115 = 1.15^x
Taking log of both sides, it becomes
log 4.115 = xlog1.15
0.614 = 0.061x
x = 0.614/0.061
x = 10 months
It will take 10 months