Originally Posted by ultramarina
DD just brought home a giant packet of graded work (happens every few weeks). They are doing multidigit multiplication problems, which she is finding easy. Worksheet after worksheet of what basically adds up to 465 x 56 (some are word problems). Except they like to throw in one per page like this:

X county has 5,678 citizens. Y county has about 8 times as many citizens as X county. About how many people live in Y county?

DD (who just did 15 other problems along the lines of "What is 3676 x 14?"): 45,424 citizens.

WRONG!

(The answer is 48,000 citizens, of course. "ABOUT how many people." Get it? Yeah, I almost feel like they put these in just to ding the kids who are zipping through.)

There must have been 4 worksheets like this; every problem was straight-ahead nonestimation multiplication except for one or two questions where they threw in an "about." DD got every single "about" one wrong, having done the actual problem (correctly). Now, I get that reading carefully is important. But meh.

The bigger problem here is the author's incorrect assumption that only citizens live in a place.

Even setting that aside, if they're going to teach estimation, they should at least teach it responsibly. Rounding is only helpful if you're rounding to a useful degree of precision. In this case, it's far more useful to round up to 5700 than to 6000.

I mean, yeah, I could just round up all my monthly bills to the nearest hundred instead of the nearest tens. That'd sure make budgeting for movie night a lot more exciting.