Sean bought 126 yellow and green balloons for a party. The number of green balloons was ²₇ times as many as the number of yellow balloons. Sean used ¹₄ times as many green balloons as yellow balloons and was left with twice as many green balloons as yellow balloons. How many balloons did Sean have in the end?

	Green (1)	Yellow (2)	Make b the same. (2)x2 = (3)
Before	28	98	196
Change	- 1 p	- 4 p	- 8 p
After	2 b	1 b	2 b

Number of green balloons that Sean bought at first = 2 u
Number of yellow balloons that Sean bought at first = 7 u

Total number of balloons at first
= 2 u + 7 u
= 9 u

9 u = 126

1 u = 126 ÷ 9 = 14

Number of green balloons at first
= 2 u
= 2 x 14
= 28

Number of yellow balloons at first
= 7 u
= 7 x 14
= 98

28 - 1 p = 2 b --- (1)
98 - 4 p = 1 b --- (2)

(2)_x2
196 - 8 p = 2 b --- (3)

(3) = (1)
196 - 8 p = 28 - 1 p
8 p - 1 p = 196 - 28 
7 p = 168

1 p = 168 ÷ 7 = 24

Number of balloons that Sean used
= 1 p + 4 p
= 5 p
= 5 x 24
= 120

Number of balloons that Sean had in the end
= 126 - 120
= 6

Answer(s): 6