Adam has 400 red stickers and blue stickers.
55% of them are red stickers and the rest are blue stickers.
When Adam buys more red stickers,
90% of the stickers are red stickers.
How many stickers does Adam buy?
|
Red |
Blue |
Before |
11 x 1 = 11 u |
9 x 1 = 9 u |
Change |
+ ? |
No change |
After |
9 x 9 = 81 u |
1 x 9 = 9 u |
55% =
55100 =
112090% =
90100 =
910 The number of blue stickers remains unchanged.
Make the number of blue stickers the same using the LCM of 9 and 1.
LCM of 9 and 1 = 9
Total number of stickers at first
= 11 u + 9 u
= 20 u
20 u = 400
1 u = 400 ÷ 20 = 20
Number of stickers that Adam buys
= 81 u - 11 u
= 70 u
= 70 x 20
= 1400
Answer(s): 1400