Adam has red and blue stickers in the ratio of 7 : 2.
He has 50 more red stickers than blue stickers.
- How many stickers does Adam have?
- If Adam gives away 20 red stickers, what is the new ratio of the number of red stickers to blue stickers?
(a)
Number of red stickers = 7 u
Number of blue stickers = 2 u
Number of more red stickers than blue stickers
= 7 u - 2 u
= 5 u
5 u = 50
1 u = 50 ÷ 5 = 10
Number of stickers that Adam has
= 7 u + 2 u
= 9 u
= 9 x 10
= 90
(b)
Number of red stickers after Adam gives away 20
= 7 u - 20
= 7 x 10 - 20
= 70 - 20
= 50
Number of blue stickers
= 2 u
= 2 x 20
= 20
New ratio of the number of red stickers to blue stickers
50 : 20
(÷ 10) 5 : 2
Answer(s): (a) 90; (b) 5 : 2