A equation to represent this situation is:

Now we have to find x.
Step 1: Subtract 0.5x from both sides.
0.75x+7.5−0.5x=0.5x+10−0.5x0.25x+7.5=10
Step 2: Subtract 7.5 from both sides.
0.25x+7.5−7.5=10−7.50.25x=2.5
Step 3: Divide both sides by 0.25.
0.25x/0.25=2.5/0.25
Answer:
x=10
They will cost the same after 10 rides.