There were some purple, grey and brown files in a box.
19 of the files were grey. The ratio of the number of purple files to the number of brown files was 3 : 5. There were 304 fewer grey files than brown files.
- Find the ratio of the number of purple files to the number of grey files to the number of brown files in the box.
- How many brown files were there?
Grey |
Purple |
Brown |
Total |
1 |
8 |
9 |
|
3 |
5 |
|
1 u |
3 u |
5 u |
9 u |
(a)
Purple : Grey : Brown
3 : 1 : 5
(b)
Number of fewer grey files than brown files
= 5 u - 1 u
= 4 u
4 u = 304
1 u = 304 ÷ 4 = 76
Number of brown files
= 5 u
= 5 x 76
= 380
Answer(s): (a) 3 : 1 : 5; (b) 380