My question is this: Is it reasonable to say that the answer for 63*11 lies between 60*10 and 65*15. To which number do you think the answer is closer? I say it is closer to 65*15 is this right?

3 answers

I disagree with you.

Although 65 is closer to 63, 10 is a lot closer to 11.
Thank you.
You're welcome.