To determine who spent more time writing per problem, we need to calculate the unit rate of minutes per problem for both Sonia and Maryna.
Sonia's Data:
- (6 problems, 120 minutes) → \( \frac{120 \text{ minutes}}{6 \text{ problems}} = 20 \text{ minutes/problem} \)
- (18 problems, 360 minutes) → \( \frac{360 \text{ minutes}}{18 \text{ problems}} = 20 \text{ minutes/problem} \)
- (25 problems, 500 minutes) → \( \frac{500 \text{ minutes}}{25 \text{ problems}} = 20 \text{ minutes/problem} \)
- (60 problems, 1,200 minutes) → \( \frac{1200 \text{ minutes}}{60 \text{ problems}} = 20 \text{ minutes/problem} \)
Maryna's Data:
- (8 problems, 200 minutes) → \( \frac{200 \text{ minutes}}{8 \text{ problems}} = 25 \text{ minutes/problem} \)
- (15 problems, 375 minutes) → \( \frac{375 \text{ minutes}}{15 \text{ problems}} = 25 \text{ minutes/problem} \)
- (20 problems, 500 minutes) → \( \frac{500 \text{ minutes}}{20 \text{ problems}} = 25 \text{ minutes/problem} \)
- (50 problems, 1,250 minutes) → \( \frac{1250 \text{ minutes}}{50 \text{ problems}} = 25 \text{ minutes/problem} \)
Comparison:
- Sonia: 20 minutes per problem
- Maryna: 25 minutes per problem
Conclusion: Maryna spent more time writing per problem at the unit rate of 25 minutes per problem.
So the correct response would be:
Maryna spent more time writing per problem at the unit rate of 25 min. 1 problem.