There were some pink, purple and grey pencils in a box.
19 of the pencils were purple. The ratio of the number of pink pencils to the number of grey pencils was 3 : 5. There were 272 fewer purple pencils than grey pencils.
- Find the ratio of the number of pink pencils to the number of purple pencils to the number of grey pencils in the box.
- How many grey pencils were there?
Purple |
Pink |
Grey |
Total |
1 |
8 |
9 |
|
3 |
5 |
|
1 u |
3 u |
5 u |
9 u |
(a)
Pink : Purple : Grey
3 : 1 : 5
(b)
Number of fewer purple pencils than grey pencils
= 5 u - 1 u
= 4 u
4 u = 272
1 u = 272 ÷ 4 = 68
Number of grey pencils
= 5 u
= 5 x 68
= 340
Answer(s): (a) 3 : 1 : 5; (b) 340