# base-ten

#### hobbit

##### New member
Hi,I'm trying to help my 3rd grader w/homework, and math is definitely not my subject, and I would sure appreciate some help. I know on this base-ten that the big sq. stands for 100, long skinny for 10 & small single for ones. But this ? I can't figure. How could you use base-ten blocks to model 527 if you did not have any hundreds? Thanks Bunches!!

#### mmm4444bot

##### Super Moderator
Staff member
hobbit said:
How could you use base-ten blocks to model 527 if you did not have any [hundreds blocks] ?

Stick 10 of the long skinny rectangles together, and the result will be the big square representing 100, yes?

I mean, 10 × 10 = 100

If you were to do this five times, you would have five big squares, and together they total 500.

In other words, taking 527, we can break up the first 500 into 50 tens.

527 = 500 + 20 + 7

= (50 × 10) + (2 × 10) + (7 × 1)

= (52 × 10) + (7 × 1)

This shows that 527 can be modeled using 52 long skinny rectangles and 7 little squares.

There are other ways to combine multiples of 10 and 1, too.

I mean, if you run out of long skinny rectangles (say you had only 40 to work with), you could also build a big square using 100 little squares.

527 = 400 + 127

= (4 × 10) + (127 × 1)

This particular modeling of 527 requires 40 long skinny rectangles and 127 little squares.

This is not much different than making change with paper money.

If I need to pay you \$527, I can give you 52 tens and 7 ones OR I can give you 40 tens and 127 ones.

Cheers ~ Mark