daniel had some stickers. he gave 2/5 to his neighbors and 5/9 of the remainder to his sister. if he had 80 stickers left, how many stickers did he have at first?

Sagot :

1 - 2/5 = 3/5
1 - 5/9 = 4/9

80 * 9/4 * 5/3 = 300

300 stickers at first
Total stickers: x
Given to neighbor: 2/5(x)
Remaining stickers: (5/5 - 2/5)x  = 3/5 (x)
Given to sister:  (5/9) (3/5) (x)  or 1/3(x)

Equation:  
x - (2/5 + 1/3)x = 80
x - (6/15 + 5/15)x = 80
x - (11/15)x = 80

LCD: 15
x(15) - (15)(11/15)x = 80 (15)
15x - 11x = 1,200
4x = 1,200
4x/4 = 1,200
x = 300

Answer:  Daniel had 300 stickers at first.