Eric bought 120 grey and blue balloons for a party. The number of blue balloons was ³₅ times as many as the number of grey balloons. Eric used ¹₄ times as many blue balloons as grey balloons and was left with twice as many blue balloons as grey balloons. How many balloons did Eric have in the end?

	Blue (1)	Grey (2)	Make b the same. (2)x2 = (3)
Before	45	75	150
Change	- 1 p	- 4 p	- 8 p
After	2 b	1 b	2 b

Number of blue balloons that Eric bought at first = 3 u
Number of grey balloons that Eric bought at first = 5 u

Total number of balloons at first
= 3 u + 5 u
= 8 u

8 u = 120

1 u = 120 ÷ 8 = 15

Number of blue balloons at first
= 3 u
= 3 x 15
= 45

Number of grey balloons at first
= 5 u
= 5 x 15
= 75

45 - 1 p = 2 b --- (1)
75 - 4 p = 1 b --- (2)

(2)_x2
150 - 8 p = 2 b --- (3)

(3) = (1)
150 - 8 p = 45 - 1 p
8 p - 1 p = 150 - 45 
7 p = 105

1 p = 105 ÷ 7 = 15

Number of balloons that Eric used
= 1 p + 4 p
= 5 p
= 5 x 15
= 75

Number of balloons that Eric had in the end
= 120 - 75
= 45

Answer(s): 45