Adam has some red stickers and blue stickers.
If 241 red stickers are removed, 90% of the stickers will be blue stickers.
If 97 red stickers are added, 25% of the stickers will be blue stickers.
- How many red stickers are there?
- How many blue stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Red |
Blue |
Red |
Blue |
Before |
1 u + 241 |
9 u |
27 u - 97 |
9 u |
Change |
- 241 |
No change |
+ 97 |
No change |
After |
1x1 = 1 u |
9x1 = 9 u |
3x9 = 27 u |
1x9 = 9 u |
(a)
90% =
90100 =
91025% =
25100 =
14Scenario 1 Fraction of the stickers that are red in the end
= 1 -
910 =
110 Scenario 2
Fraction of the stickers that are red in the end
= 1 -
14 =
34 The number of blue stickers remains unchanged in both scenarios.
LCM of 9 and 1 = 9
27 u - 97 = 1 u + 241
27 u - 1 u = 241 + 97
26 u = 338
1 u = 338 ÷ 26 = 13
Number of red stickers
= 1 u + 241
= 1 x 13 + 241
= 13 + 241
= 254
(b)
Number of blue stickers
= 9 u
= 9 x 13
= 117
Answer(s): (a) 254; (b) 117