Sometimes you want to be able to get an approximate answer quickly and you don't need to know the exact answer to a problem. There are different strategies that people use to get approximate answers quickly. In this lesson we will use one simple way of estimating an answer.
PROBLEM: 333 / 32 =
STRATEGY:
1) round the dividend to the nearest 100
2) round the divisor to the nearest 10
3) forget about the remainder
ROUNDED PROBLEM: 300 / 30 = 10
The actual answer to this problem is 10 r13 and so our estimate of
10 is really fairly close to the actual answer.
Now take a look at these examples.
PROBLEM: 435 / 28 =
STRATEGY: round divisor to nearest 10, dividend to nearest 100
and forget about the remainder.
ROUNDED PROBLEM: 400 / 30 = 13
The actual answer to this problem is 15 r15 which isn't too far
away from our rounded answer.
Try a few for yourself!