Andy had 170 more stickers than Sean. Andy gave 20% of his stickers to Sean. Sean in return gave 50% of his stickers to Andy. In the end, Andy had 416 more stickers than Sean. How many stickers did Andy have at first?
| |
Andy |
Sean |
Comparing Andy
and Peter at first |
170 more |
|
| Before |
5 u + 170 |
5 u |
| Change 1 |
- 1 u - 34 |
+ 1 u + 34 |
| After 1 |
4 u + 136 |
6 u + 34 |
| Change 2 |
+ 3 u + 17 |
- 3 u - 17 |
| After 2 |
7 u + 153 |
3 u + 17 |
20% =
20100 =
1520% x 170
=
20100 x 170
= 34
50% x 34
=
50100 x 34
= 17
50% x 6 u
=
50100 x 6 u
= 3 u
Andy had 416 more stickers than Sean in the end. If another 416 stickers are given to Sean, both will have the same number of stickers.
7 u + 153 = 3 u + 17 + 416
7 u - 3 u = 17 + 416 - 153
14 u = 280
1 u = 280 ÷ 14 = 20
Number of Andy's stickers at first
= 5 u + 170
= 5 x 20 + 170
= 100 + 170
= 270
Answer: 270
