A shop sells bicycles and tricycles. In total there are 9 cycles (cycles include both bicycles and tricycles) and 21 wheels. Determine how many of each there are, if a bicycle has two wheels and a tricycle has three wheels.	Options: A) b=2,t=3 B) b=5,t=3 C) b=6,t=3 D) b=2,t=5 E) b=3,t=4
Let b be the number of bicycles and let t be the number of tricycles.   Set up the equations   b+t=9............(1)   2b+3t=21............(2)   Rearrange equation (1) and substitute into equation (2)   2b+27-3b=21   -b=-6   b=6   Calculate the number of tricycles t   t=9−b   =9−6   =3   There are 3 tricycles and 6 bicycles.   Answer is b=6,t=3.
<result>C</result>
A shop sells bicycles and tricycles. In total there are 9 cycles (cycles include both bicycles and tricycles) and 21 wheels. Determine how many of each there are, if a bicycle has two wheels and a tricycle has three wheels.