Fill in the blanks.
For (a) to (c), give the answers in units (Eg 1 u) or unit equations (Eg 1 u + 2).
Adam has some stickers.
He has 20 less red stickers than blue stickers.
He has 60 less green stickers than
the sum of the number of red and blue stickers.
- How many more green stickers than blue stickers are there?
- How many less red stickers than green stickers are there?
- How many blue and green stickers are there?
(a)
Choose the smallest group to be 1 u.
Number of red stickers = 1 u
Number of blue stickers = 1 u + 20
Number of blue and red stickers
= 1 u + 1 u + 20
= 2 u + 20
Number of green stickers
= 2 u + 20 - 60
= 2 u - 40
Number of more green stickers than blue stickers
= (2 u - 40) - (1 u + 20)
= 2 u - 40 - 1 u - 20
= 2 u - 1 u - 40 - 20
= 1 u - 60
(b)
Number of less red stickers than green stickers
= (2 u - 40) - 1 u
= 2 u - 40 - 1 u
= 2 u - 1 u - 40
= 1 u - 40
(c)
Number of blue and green stickers
= (1 u + 20) + (2 u - 40)
= 1 u + 2 u + 20 - 40
= 3 u - 20
Answer(s): (a) 1 u - 60; (b) 1 u - 40; (c) 3 u - 20