Question

Kate has blue fish and yellow fish . The ratio of blue fish to yellow fish is (3 : 21) . She has 63 yellow fish . How mane blue fish does she have ?

Answer 1

Answer:

I love using model drawing for ratio problems. Check out the video to see how this strategy works. If you do not like model drawing, another method would be:

red : yellow

1 : 2 (they tell you that the actual number of red fish is 3 so I change the 1 to a 3)

3 : ___ (the one became a 3 but multiplying by 3. In order to keep the ratios equivalent you have

to multiply the other side by 3 as well... just like in fractions! 2 x 3 = 6

3:6

This means that when there are three red fish, there will then be 6 yellow fish.