I was going over a standardized test question involving percentages. The question is as follows

The answer to this problem is 24.In June a baseball team that had played 60 games had won 30% of its games played.Later after a winning streak the team raised the average to 50%.

How many games must the teams have won in a row to attain this average ?

I cant manage to find out how they got 24 as the answer. Any suggestion would be appreciated. One reason i cant figure this out is because it doesnt state how many games they played later on ... I might be wrong. Any help would be appreciated.