In Numbers Reactions you'll have a short amount of time each round to blow up the bubbles and a certain amount of bubbles you're trying to pop. At first it starts pretty easy but before long you'll need to know how to do a combo explosion. In order to do this you have to find successive numbers like 5-6-7 and pop them all in a row to start a chain reaction of explosions and pop more bubbles in a shorter amount of time. You can hit more than three numbers in succession as well and it will be even more successful. The second best way to pop is to hit a bubble while it's close to another.