Question: Max has $35 a day to spend on windsurfing and snorkelling and he can spend as much time as he likes doing them. The price of renting equipment for windsurfing is $10 an hour and for snorkelling is $5 an hour. The table shows the total utility Max gets from each activity.
Hours per day Total utility from Total utility from
windsurfing snorkelling
1 120 40
2 220 76
3 300 106
4 360 128
5 396 140
6 412 150
7 422 158
Calculate Max's marginal utility from windsurfing at each number of hours per day. Does Max's marginal utility from windsurfing obey the principle of diminishing marginal utility?