Katy makes coffee using teaspoons of sugar and cups of water in the ratio of 7:13. If she used a total of 120 teaspoons of sugar and cups of water, calculate the number of teaspoonfuls of sugar she used.
The total ratio representing the ingredients she used to make the coffee is 7+13 = <<7+13=20>>20
Since the fraction representing the number of teaspoons she used is 7/20, she used 7/20*120 = <<7/20*120=42>>42
#### 42