Adam has 280 red stickers and blue stickers.
90% of them are red stickers and the rest are blue stickers.
When Adam gives away some red stickers,
30% of the remaining stickers are red stickers.
How many stickers does Adam give away?
|
Red |
Blue |
Before |
9 x 7 = 63 u |
1 x 7 = 7 u |
Change |
- ? |
No change |
After |
3 x 1 = 3 u |
7 x 1 = 7 u |
90% =
90100 =
91030% =
30100 =
310 The number of blue stickers remains unchanged.
Make the number of blue stickers the same using the LCM of 1 and 7.
LCM of 1 and 7 = 7
Total number of stickers at first
= 63 u + 7 u
= 70 u
70 u = 280
1 u = 280 ÷ 70 = 4
Number of stickers that Adam gives away
= 63 u - 3 u
= 60 u
= 60 x 4
= 240
Answer(s): 240