Adam has blue and red stickers in the ratio of 7 : 5.
He has 80 more blue stickers than red stickers.
- How many stickers does Adam have?
- If Adam gives away 30 blue stickers, what is the new ratio of the number of blue stickers to red stickers?
(a)
Number of blue stickers = 7 u
Number of red stickers = 5 u
Number of more blue stickers than red stickers
= 7 u - 5 u
= 2 u
2 u = 80
1 u = 80 ÷ 2 = 40
Number of stickers that Adam has
= 7 u + 5 u
= 12 u
= 12 x 40
= 480
(b)
Number of blue stickers after Adam gives away 30
= 7 u - 30
= 7 x 40 - 30
= 280 - 30
= 250
Number of red stickers
= 5 u
= 5 x 30
= 200
New ratio of the number of blue stickers to red stickers
250 : 200
(÷ 50) 5 : 4
Answer(s): (a) 480; (b) 5 : 4