Adam has 120 stickers.
He has 10 less green stickers than blue stickers.
He has 40 less red stickers than green stickers.
How many less red stickers than blue and green stickers does Adam have?
Choose the smallest group to be 1 u.

Number of red stickers = 1 u
Number of green stickers = 1 u + 40
Number of blue stickers = 1 u + 40 + 10 = 1 u + 50

Total number of stickers
= 1 u + 1 u + 40 + 1 u + 50
= 3 u + 90

3 u + 90 = 120
3 u = 120 - 90
3 u = 30

1 u = 30 ÷ 3 = 10

Total number of blue and green stickers
= 1 u + 40 + 1 u + 50
= 2 u + 90

Number of less red stickers than blue and green stickers
= 2 u + 90 - 1 u
= 2 u - 1 u + 90
= 1 u + 90
= 10 + 90
= 100

Answer(s): 100