45 is 90% of what number? be as specific as possible. : -)

Frist you have to set up an equation. You know that 90 % is out of a 100 so that's one fraction. The rule for word equations like these is: is over of so therefore 45 is on top.

45         90
                    Now all you do is cross multiply so 45 x100= 4500
n           100           then 4500/90 to get n 

                                                                                                      

20000 as first it increases by 2500 then by 5000 so next it will increase by 10000