Adam has 3 times as many green stickers as red stickers.
He buys another 90 red stickers.
Adam has equal number of green and red stickers.
- How many more green stickers than red stickers does Adam have at first?
- How many red stickers and green stickers does Adam have in the end?
|
Green |
Red |
Before |
3 x 1 = 3 u |
1 x 1 = 1 u |
Change |
No Change |
+ 90 |
After |
1 × 3 = 3 u |
1 × 3 = 3 u |
(a)
The number of green stickers Adam has at first and in the end remains unchanged.
Make the number of green stickers the same using the LCM of 1 and 3.
LCM of 1 and 3 = 3
Number of red stickers that Adam buys
= 3 u - 1 u
= 2 u
2 u = 90
1 u = 90 ÷ 2 = 45
Number of more green stickers than red stickers at first
= 3 u - 1 u
= 2 u
= 2 x 45
= 90
(b)
Number of red stickers and green stickers in the end
= 3 u + 3 u
= 6 u
= 6 × 45
= 270
Answer(s): (a) 90; (b) 270