That is true. The best is to say I do not know. I was about to, but I did not want to disappoint you all.Yes, it is a reasonable estimate. YOU said it was. I just asked why!!
Now you want to know why it is a reasonable estimate.
The least mileage would have come from going the slowest speeds. This mileage would have been 40mph*3hrs + 20 mph*1hr = 120miles + 20 miles = 140 miles.
The highest mileage would have come from going the highest speeds. This mileage would have been 60mph*3hrs + 40 mph*1hr = 180miles + 40 miles = 220 miles.
Your answer fell in between 140 miles and 220 miles making it a reasonable answer. In fact, in my opinion, any mileage from 140 miles to 180 miles would have been reasonable.
Now if you had asked why 180 miles was reasonable I would have answered your question but instead you stated that you felt that your answer was reasonable when it turns out that you had no idea if it was reasonable or not. The problem here is if you say things that are not true it can in the end cause trouble.
If you want to say something - say it. The more tutors know about your thinking, the better they can help.That is true. The best is to say I do not know. I was about to, but I did not want to disappoint you all.
Thanks a lot. Noted!.If you want to say something - say it. The more tutors know about your thinking, the better they can help.
Regarding this problem - if you are not sure whether you are interpreting the question correctly it's always ok to provide an answer that includes additional assumptions. E.g. "If the author of the question meant 'average' by reasonable, then my answer is this. If the author meant that I could pick any number between the minimum and maximum, then my answer is this, etc".