Question

Mr Lim put some red pens and blue pens into a box . The ratio of the number of red pens to the number of blue pens was 3: 4 .He pet another 20 red pens into the box and the ratio of the number of red pens to the number of blue pens became 2:1 (a) How many red pens were there in the end? (b) How many blue pens were there?

Answer 1

Answer:

a) There were 32 red pens and b) 16 blue pens.

Step-by-step explanation:

3:4

for 3:4 to be 2:1 we should add 5 in order for it to be 8:4 (2:1)

20 divided by 5 is equal to 4

8:4

8 times 4 is equal to 32

4 times 4 is equal to 16