Adam has blue and red stickers in the ratio of 7 : 5.
He has 90 more blue stickers than red stickers.
- How many stickers does Adam have?
- If Adam gives away 40 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 = 90
1 u = 90 ÷ 2 = 45
Number of stickers that Adam has
= 7 u + 5 u
= 12 u
= 12 x 45
= 540
(b)
Number of blue stickers after Adam gives away 40
= 7 u - 40
= 7 x 45 - 40
= 315 - 40
= 275
Number of red stickers
= 5 u
= 5 x 40
= 225
New ratio of the number of blue stickers to red stickers
275 : 225
(÷ 25) 11 : 9
Answer(s): (a) 540; (b) 11 : 9