It's not always easy to see how many times a two-digit number goes into a larger one. One useful trick is to round to the nearest multiple of 10 to make guessing easier. This comes in handy for smaller division problems, or for parts of a long division problem. For example, let's say we're solving 143 ÷ 27, but we don't have a good guess at how many times 27 goes into 143. Let's pretend we're solving 143 ÷ 30 instead. In our example, we can count by 30s instead of counting by 27s. Counting by 30 is pretty easy once you get the hang of it: 30, 60, 90, 120, 150.  If you find this difficult, just count by threes and add a 0 to the end. Count until you get higher than the larger number in the problem (143), then stop. We didn't hit 143 exactly, but we got two numbers close to it: 120 and 150. Let's see how many fingers we counted on to get them:  30 (one finger), 60 (two fingers), 90 (three fingers), 120 (four fingers). So 30 x four = 120. 150 (five fingers), so 30 x five = 150. 4 and 5 are the two most likely answers to our problem. Now that we have two good guesses, let's try them out on the original problem, which was 143 ÷ 27:  27 x 4 = 108 27 x 5 = 135 Since both our numbers ended up below 143, let's try getting even closer by trying one more multiplication problem:  27 x 6 = 162. This is higher than 143, so it can't be the right answer. 27 x 5 came closest without going over, so 143 ÷ 27 = 5 (plus a remainder of 8, since 143 - 135 = 8.)
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