Final answer:
Creek exercises 310 more minutes than Myna in a month with 31 days.
Step-by-step explanation:
To find the difference in the number of minutes Creek exercises compared to Myna in a month, we need to calculate the total number of minutes each of them exercises in a month.
Myna exercises for 30 minutes each day, so in one month (31 days), she exercises for: 30 minutes/day x 31 days = 930 minutes
Creek exercises for 40 minutes each day, so in one month (31 days), he exercises for: 40 minutes/day x 31 days = 1,240 minutes
To find the difference, we subtract the number of minutes Myna exercises from the number of minutes Creek exercises: 1,240 minutes - 930 minutes = 310 minutes