it would depend how much you actually used, but you would take the amount you used and divide it by the total amount of yarn. so if the yarn was 4m long and you used 2m then it would be 2/4 which is 0.5 which is also 50%, so half the yarn was used.
This should be the right answer though. If you go to desmos.com and type in the equations it gives you the answer.
Hope that helps :)
Thats is a simple fraction:
30/10 = 3/1 = 3
so 30 tens equals 3
- 16 in factored form is;
(3x + 4)(3x - 4)
hope that helps :D
It would be 709 if u add them up