In order to compare the amount of wax, you have to calculate the volume of both candles.
Candle of booth A = πr² h/3
A = π 4² 6/3
A = π 16 2
A = 32π
Now, Candle of Booth B = π 5² 5/3
B = π 25 5/3
B = 41.6π
In short, Booth B sells the candle with more wax.
Hope this helps!