a company having two branches located at abuja and lagos both of which have sales of 50,000 in the first month of trading.if abuja's sales increase each month at the rate of 7,500 per month and lagos sales increase at the rate of 10% per month on the previous month sales.What will be their combined sales in the

Question

(a)twelveth month of trading
(b)first year of operation

Answer 1

this is just like simple vs compound interest.
A: 50000 + 7500m (arithmetic progression)
B: 50000 * 1.10^m (geometric progression)
So plug in your numbers.
Come back if you get stuck.

Answer 2

thanks @oobleck, should i solve with this formula Tn=a+(n-1)d

Answer 3

for the AP, yes.

Answer 4

my answer for the twelveth month of trading is #132,500.
Am still finding it difficult to get the first year of operation :-(