Vaidev has a total of 68 of red and yellow files.
16 of the red files and half of the yellow files are new. How many of his yellow files are new if he has a total of 14 new files?
|
Red files |
Yellow files |
Total |
Total |
6 u |
2 p |
68 |
New |
1 u |
1 p |
14 |
Old |
5 u |
1 p |
54 |
Number of old files
= 68 - 14
= 54
1 u + 1 p = 14 --- (1)
5 u + 1 p = 54 --- (2)
(2) - (1)
(5 u + 1 p) - (1 u + 1 p) = 54 - 14
5 u - 1 u = 40
4 u = 40
1 u = 40 ÷ 4 = 10
Number of new yellow files
= 14 - 1 u
= 14 - 10
= 4
Answer(s): 4