There were some silver, blue and red notebooks in a box.
19 of the notebooks were blue. The ratio of the number of silver notebooks to the number of red notebooks was 3 : 5. There were 256 fewer blue notebooks than red notebooks.
- Find the ratio of the number of silver notebooks to the number of blue notebooks to the number of red notebooks in the box.
- How many red notebooks were there?
Blue |
Silver |
Red |
Total |
1 |
8 |
9 |
|
3 |
5 |
|
1 u |
3 u |
5 u |
9 u |
(a)
Silver : Blue : Red
3 : 1 : 5
(b)
Number of fewer blue notebooks than red notebooks
= 5 u - 1 u
= 4 u
4 u = 256
1 u = 256 ÷ 4 = 64
Number of red notebooks
= 5 u
= 5 x 64
= 320
Answer(s): (a) 3 : 1 : 5; (b) 320