A man accepts a position at Php9000 a month with the understanding that he will receive an increase of 10% a year computed on the previous years salary. Form an equation that will compute how much he will receive a month after 10 years of service.

I will assume that the salary increases annually and is then divided by 12 (that's what they used to do to mine)

at start, annual salary = Php 108000
end of year 1 : 108000(1.10) = 118800
end of year 2 : 108000(1.10)^2 = 130680
...
end of year 10 = 108000(1.10)^10 = 280124.19
so monthly salary after 10 years
= ( 108000(1.10)^10 ) /12
= 23343.68