Think about it a little broader... The listed times were an hour and 15 minutes and 59 seconds, 1 hour 47 minutes and16 seconds, etc... These represent a definite time value. One length of time. If you want to do statistics on these times, it isn't going to work to break them into partial times.

Agree, the maths in the answers seem to be off.

Did you read the description?

The function's name should be points, not sum_points. Don't rename the function, it won't work.