Answer :

the answer is 21 all you had to do was multiply 7 by 3
There are three thirds to make one whole. So, you would multiply 7 by 3 and you get 21 There are 21 thirds in 7 You can check this by multiplying 21 by 3 and you will get 7. Hope this helped :) Have a nice day( I forget it is night already , sorry.)