[jimtorr]

It’s a trick the mind plays. We know that the answer starts with 200, and that 50/2 is 25, so immedietly the mind goes to 225.

Full disclosure: I thought 225 as well. At least I recognize the mind trick, and am not baffled.

[ridesthemiles]

NO mind trick for me-—but then-—I WENT TO A ONE ROOM GRADE SCHOOL

[Pollard]

Yep, 225 popped into my head for a second and then I got 275 a second later.

When we homeschooled the kids, they didn't get calculators. They learned long division too. Never could get my daughter to memorize multiplication tables though and I only asked for up to 10 x 10. I know them up to 12 x 12 because I'm blue collar and use inches/feet and knowing how many inches are in 1 - 12 feet is handy. I also know my decimal equivalents by heart down to the 16th of an inch and can figure out/remember the 32nds from there.

Daughter always kept one of these handy.

I had her make the table but with 0 in the bottom left corner, AutoCAD style. Tried flash cards and was hoping having her make and reference the table would help her remember but she refused. It was a rebellious thing. Because she knew I wanted her to learn it, she refused. Didn't matter if it was for her own good.

[nitzy]

I am glad that someone else was honest about.

It’s not that I couldn’t figure out the answer. It is more that it seemed easy enough at first glance that it activate my analytical brain and instead allowed my instinctive brain to try first.

[Yardstick]

Same here. Thought 225 then caught myself. It’s sort of the math equivalent of a tongue twister.

[BRL]

I also thought 225 but then i knew it was probably wrong and rethought for a minute and knew it was 275. Your ex0lanation is good.