Each month Terry earns some money. He spends $120 on food and $95 on transport. He spends 2/5 of the remaining money on a new suit. He has $780 left. How much money does Terry earn in a month?
+128475 Let E be what he earns per month
So
E - 120 - 95 =
E - 215 is what he has left after the food and transport
And then he spends (2/5) of what's left
(2/5)(E -215)
So
(E -215) - (2/5) (E - 215) = 780
(3/5) (E -215) = 780
E - 215 = 780 (5/3)
E - 215 = 1300
E = 1300 + 215 = $1515
