[] The fractions are
[] I see that 21 is a multiple of 7, so this one will be simple to solve.
-> 21 / 7 = 3, so we can do the following:
[] Now they have a common denominator of <u>21</u>
Have a nice day!
I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)
- Heather