Charles and Lily had the same number of sweets. After Lily gave away 15 sweets and Charles gave away 45 sweets, Lily had 4 times as many sweets as Charles. How many sweets did each of them have at first?

Answer 1

number of sweets for Charles --- x
number of sweets for Lildy ---- x

after give-away:
Charles had x-45
Lily had x - 15

x - 15 = 4(x - 45)
x - 15 = 4x - 180
continue solving for x