Archie and John had 189 staplers together. Archie had 15 more staplers than John. Both of them sold some of their staplers. John sold 10% less staplers than what Archie sold. In the end, John had half as many staplers left as Archie. How many staplers had Archie left?
| |
Archie
(1) |
John
(2) |
Make p the same
(2)x2 = (3) |
Comparing Archie
and John at first |
15 more |
|
|
| Before |
102 |
87 |
174 |
| Change |
- 10 u |
- 9 u |
- 18 u |
| After |
2 p |
1 p |
2 p |
Number of staplers that John had at first
= (189 - 15) ÷ 2
= 174 ÷ 2
= 87
Number of staplers that Archie had at first
= 87 + 15
= 102
Number of staplers that John sold in percent
= 100% - 10%
= 90%
90% =
90100 =
910 Make p the same.
(1) = (3)
102 - 10 u = 174 - 18 u
18 u - 10 u = 174 - 102
8 u = 72
1 u = 72 ÷ 8 = 9
Number of staplers that Archie had left
= 102 - 10 u
= 102 - 10 x 9
= 102 - 90
= 12
Answer(s): 12
