There were some red, green and yellow pens in a box.
213 of the pens were green. The ratio of the number of red pens to the number of yellow pens was 4 : 7. There were 350 fewer green pens than yellow pens.
- Find the ratio of the number of red pens to the number of green pens to the number of yellow pens in the box.
- How many yellow pens were there?
Green |
Red |
Yellow |
Total |
2 |
11 |
13 |
|
4 |
7 |
|
2 u |
4 u |
7 u |
13 u |
(a)
Red : Green : Yellow
4 : 2 : 7
(b)
Number of fewer green pens than yellow pens
= 7 u - 2 u
= 5 u
5 u = 350
1 u = 350 ÷ 5 = 70
Number of yellow pens
= 7 u
= 7 x 70
= 490
Answer(s): (a) 4 : 2 : 7; (b) 490