Answer:
70/2
Step-by-step explanation:
We have a population of 200 people
Growth rate = 2%
How long it will take for the population to double
Double the population = 2× 200 = 400
The formula for Exponential growth =
y = a(1 + r)^t
y = Value at time t = 400
a = Initial value = 200
r = 2% = 0.02
t = ?
Hence:
400 = 200 ( 1 + 0.02)^t
Divide both sides by 200
400/200 = 200 ( 1 + 0.02)^t/200
2 = (1.02)^t
Take logarithm of both sides
log 2 = log(1.02)^t
log 2 = t log 1.02
t = log 2/log 1.02
t = 35.003417942
Approximately t = 35
We have so many formula to calculate doubling time
t = 70/Growth rate
From the above question
Growth rate = 70/2%
= 35
Therefore, the equation that we use to calculate how long it will take for the population to double to 400 people is 70/2
