Albert has a total of 34 of yellow and green pencils.
15 of the yellow pencils and half of the green pencils are new. How many of his green pencils are new if he has a total of 11 new pencils?
| |
Yellow pencils |
Green pencils |
Total |
| Total |
5 u |
2 p |
34 |
| New |
1 u |
1 p |
11 |
| Old |
4 u |
1 p |
23 |
Number of old pencils
= 34 - 11
= 23
1 u + 1 p = 11 --- (1)
4 u + 1 p = 23 --- (2)
(2) - (1)
(4 u + 1 p) - (1 u + 1 p) = 23 - 11
4 u - 1 u = 12
3 u = 12
1 u = 12 ÷ 3 = 4
Number of new green pencils
= 11 - 1 u
= 11 - 4
= 7
Answer(s): 7
