Question

If TOWN A has a yearly population of 3,225 and is growing by 100 people each year and TOWN B has a yearly population of 3,300 and is growing by 75 people per year, after how many years will the two populations be equal?

Answer 1

let N represent the year they'll be equal
so Town A arithmetic progressive expression =
tn=3225+(n-1)100
tn= 3225+100n-100 = 3125+100n

for Town B you have
tn= 3300+(n-1)75 = 3300+75n-75 = 3225+75n
equating both A and B
3125+100n=3225+75n
100n-75n=3225-3125
25n= 100
n=100÷25=4
n=4years

they'll be equal after 4years