Question

Explain how comparing 645 and 738 is different from comparing 645 and 649

Answer 1

When comparing these two sets of number, the first set is harder to find the different as you need to borrow from a column. For instance, when you start subtracting in the 10s place, you cannot take 40 away from 30.

Whereas in the second set, comparing the numbers is easy. They have the same 100s value and the same 10s value. You are simply comparing the 1s place.

Answer 2

First, if we compare 645 and 738, the difference is significant, because those number have different units, different tenths and different hundreds.

However, if we compara 645 and 649, the difference isn't significant, because they have the same hundreds, the same tenths, but different units.

So, in terms of comparing numbers as such, we can tell that the difference in each comparison is about units, tenth and hundreds difference.

From this different comparison, the difference operation (subtraction) is also different, because it's not the same to subtract 645 from 738 than from 649, the difference is higher.