To find out who spent more time writing per problem, we need to calculate the unit rate (minutes per problem) for both Sonia and Maryna using the data provided.
Sonia:
- For 6 problems: 120 minutes → \( \frac{120}{6} = 20 \) minutes per problem
- For 18 problems: 360 minutes → \( \frac{360}{18} = 20 \) minutes per problem
- For 25 problems: 500 minutes → \( \frac{500}{25} = 20 \) minutes per problem
- For 60 problems: 1200 minutes → \( \frac{1200}{60} = 20 \) minutes per problem
So, Sonia spends 20 minutes per problem.
Maryna:
- For 8 problems: 200 minutes → \( \frac{200}{8} = 25 \) minutes per problem
- For 15 problems: 375 minutes → \( \frac{375}{15} = 25 \) minutes per problem
- For 20 problems: 500 minutes → \( \frac{500}{20} = 25 \) minutes per problem
- For 50 problems: 1250 minutes → \( \frac{1250}{50} = 25 \) minutes per problem
So, Maryna spends 25 minutes per problem.
Comparison:
- Sonia: 20 minutes per problem
- Maryna: 25 minutes per problem
Thus, Maryna spent more time writing per problem at the unit rate of 25 minutes per problem.
So the correct response is:
"Maryna spent more time writing per problem at the unit rate of 25 min. 1 problem."