Solving rational equations

Question

A football team has won 13 out of 18 matches they played this session. How many additional matches must the team win in a row to raise its winning percentage to 80%?

Answer 1

The ratio of Wins to Games is currently 13/18. 

 

If they play and win x additional games (consecutively), the ratio will become (13 + x) / (18 + x) = 4/5 i.e. 80%.

 

Solve this equation for x