okay here we go!
1. I'm a visual person so i would start by drawing circles for the wheels.
o o o o o o o o o o o o o o o o o o o
2. I tried separating them by threes
ooo ooo ooo ooo ooo ooo o
2 By two's
oo oo oo oo oo oo oo oo oo o
3. then i started to count
ooo ooo ooo ooo ooo = 15 and i still had 4 left over
oo oo = 4 and that would equal to 19 wheels!
the answer is: there are 5 trikes and 2 bicycles!!!!!
Hope that helped!
:)