Ben has a total of 42 of pink and purple staplers.
13 of the pink staplers and half of the purple staplers are new. How many of his purple staplers are new if he has a total of 17 new staplers?
| |
Pink staplers |
Purple staplers |
Total |
| Total |
3 u |
2 p |
42 |
| New |
1 u |
1 p |
17 |
| Old |
2 u |
1 p |
25 |
Number of old staplers
= 42 - 17
= 25
1 u + 1 p = 17 --- (1)
2 u + 1 p = 25 --- (2)
(2) - (1)
(2 u + 1 p) - (1 u + 1 p) = 25 - 17
2 u - 1 u = 8
1 u = 8
1 u = 8 ÷ 1 = 8
Number of new purple staplers
= 17 - 1 u
= 17 - 8
= 9
Answer(s): 9
