8.3*4 = 33.2 kg.
Hopefully that is correct
Since Yi Ting weighs 8.3 and her brother is 4 times heavier you would multiply those two numbers to get the answer.
3.25y=13. Isolate y by dividing both sides of the equation by 3.25. So 3.25y/3.25=13/3.25. Your answer is therefore 13/3.25, or 4
B. is the answer all it asking you is she correct that she only has 18.25 to play with for the games.