Verified answer

It is given that

2:3,17:21,11:14 and 5:7

We can write it in fractions as

2/3,17/21,11/14,5/7

Here the LCM of 3, 21, 14 and 7 is 42

By converting the ratio as equivalent

2/3=(2×14)/(3×14)=28/42

17/21=(17×2)/(21×2)=34/42

11/14=(11×3)/(14×3)=33/42

5/7=(5×6)/(7×6)=30/42

Now writing it in ascending order

28/42,30/42,33/42,34/42

By further simplification

2/3,5/7,11/14,17/21

So we get

2:3,5:7,11:14and17:21