wikiHow is a “wiki,” similar to Wikipedia, which means that many of our articles are cowritten by multiple authors. To create this article, 49 people, some anonymous, worked to edit and improve it over time.
This article has been viewed 464,394 times.
Learn more...
Dividing by a twodigit number is a lot like singledigit division, but it does take a little longer and some practice. Since most of us haven't memorized our 47 times tables, this can take a little guesswork, but there's a handy trick you can learn to make it faster. It also gets easier with practice, so don't get frustrated if it seems slow at first.
Steps
Part 1
Part 1 of 2:Dividing by a TwoDigit Number
Download Article

1Look at the first digit of the larger number. Write the problem as a longdivision problem. Just like a simpler division problem, you can start by looking at the smaller number, and asking "Does it fit into the first digit of the larger number?"^{[1] X Research source }
 Let's say you're solving 3472 ÷ 15. Ask "Does 15 fit into 3?" Since 15 is definitely larger than 3, the answer is "no," and we move on to the next step.

2Look at the first two digits. Since you can't fit a twodigit number into a onedigit number, we'll look at the first two digits of the dividend instead, just like we would in a regular division problem. If you still have an impossible division problem, you'll need to look at the first three digits instead, but we don't need to in this example:^{[2] X Research source }
 Does 15 fit into 34? Yes, it does, so we can start calculating the answer. (The first number doesn't have to fit perfectly, it just needs to be smaller than the second number.)
Advertisement 
3Use a little guesswork. Find out exactly how many times the first number fits into the other. You might know the answer already, but if you don't, try making a good guess and checking your answer with multiplication.^{[3] X Research source }
 We need to solve 34 ÷ 15, or "how many times does 15 go into 34"? You're looking for a number you can multiply with 15 to get a number less than 34, but pretty close to it:
 Does 1 work? 15 x 1 = 15, which is less than 34, but keep guessing.
 Does 2 work? 15 x 2 = 30. This is still less than 34, so 2 is a better answer than 1.
 Does 3 work? 15 x 3 = 45, which is greater than 34. Too high! The answer must be 2.
 We need to solve 34 ÷ 15, or "how many times does 15 go into 34"? You're looking for a number you can multiply with 15 to get a number less than 34, but pretty close to it:

4Write the answer above the last digit you used. If you set this up like a long division problem, this should feel familiar.
 Since you were calculating 34 ÷ 15, write the answer, 2, on the answer line above the "4."

5Multiply your answer by the smaller number. This is the same as a normal long division problem, except we'll be using a twodigit number.^{[4] X Research source }
 Your answer was 2 and the smaller number in the problem is 15, so we calculate 2 x 15 = 30. Write "30" underneath the "34."

6Subtract the two numbers. The last thing you wrote went underneath the original larger number (or part of it). Treat this as a subtraction problem and write the answer on a new line underneath.^{[5] X Research source }
 Solve 34  30 and write the answer underneath them on a new line. The answer is 4. This 4 is still "left over" after we fit 15 into 34 two times, so we'll need to use it in the next step.

7Bring down the next digit. Just like a regular division problem, we're going to keep calculating the next digit of the answer until we've finished.^{[6] X Research source }
 Leave the 4 where it is and bring down the "7" from "3472" to make 47.

8Solve the next division problem. To get the next digit, just repeat the same steps you did above for the new problem. You can use guesswork again to find the answer:
 We need to solve 47 ÷ 15:
 47 is bigger than our last number, so the answer will be higher. Let's try four: 15 x 4 = 60. Nope, too high!
 We'll try three instead: 15 x 3 = 45. Smaller than 47 but close to it. Perfect.
 The answer is 3, so we'll write that about the "7" on the answer line.
 (If we ended up with a problem like 13 ÷ 15, with the first number smaller, we would need to bring down a third digit before we could solve it.)
 We need to solve 47 ÷ 15:

9Continue using long division. Repeat the long division steps we used before to multiply our answer by the smaller number, write the result underneath the larger number, and subtract to find the next remainder.^{[7] X Research source }
 Remember, we just calculated 47 ÷ 15 = 3, and now we want to find what's left over:
 3 x 15 = 45, so write "45" underneath the 47.
 Solve 47  45 = 2. Write "2" underneath the 45.

10Find the last digit. As before, we bring down the next digit from the original problem so we can solve the next division problem. Repeat the steps above until you find every digit in the answer.
 We've got 2 ÷ 15 as our next problem, which doesn't make much sense.
 Bring down a digit to make 22 ÷ 15 instead.
 15 goes into 22 one time, so we write "1" at the end of the answer line.
 Our answer is now 231.

11Find the remainder. One last subtraction problem to find the final remainder, then we'll be done. In fact, if the answer to the subtraction problem is 0, you don't even need to write a remainder at all.^{[8] X Research source }
 1 x 15 = 15, so write 15 underneath the 22.
 Calculate 22  15 = 7.
 We have no more digits to bring down, so instead of more division we just write "remainder 7" or "R7" at the end of our answer.
 The final answer: 3472 ÷ 15 = 231 remainder 7
Advertisement
Part 2
Part 2 of 2:Making Good Guesses
Download Article

1Round to the nearest ten. It's not always easy to see how many times a twodigit 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.^{[9] X Research source }
 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.

2Count by the smaller number on your fingers. 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.

3Find the two most likely answers. 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.

4Test those two numbers with the real 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

5Make sure you can't get any closer. 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.)
Advertisement
Community Q&A

QuestionHow to convert a mixed number fraction?DonaganTop AnswererTo convert a mixed number to an improper fraction, multiply the denominator by the whole number, and add the original numerator. That gives you the new numerator. The denominator remains unchanged, and the whole number no longer exists.

QuestionHow do I solve a problem that doesn't divide equally?DonaganTop AnswererWhatever is left over in the last step is shown as a "remainder" attached to the wholenumber quotient.

QuestionI am 89 and don't know any math. Is this a problem?DonaganTop AnswererProbably not. If you've survived this long without resorting to math, there's no reason you couldn't continue to do so. Someone considerably younger than you, however, would be well advised to learn the fundamentals of math, because they can make life easier in many ways.

QuestionWhat is strategy for 251x60?Community AnswerIf you are trying to do it mentally, do 251 x 10 which is to put an zero at the end, to get 2510, and times it by 2 to get 5020, which can be done easily, then times by 3 again to get 15060. All mentally. You times it by 2 then 3 because they are factors of 6 and give the same result. It always is much easier to times it by 2 then 3 since if you know basic multiplication tables, you should be able to do it mentally.

QuestionIn which grade would you normally learn how to divide double digits?Community AnswerI'd say between second and fourth grade, depending on class placement. My younger brother is learning that kind of thing right now, and he's in third grade.

QuestionIn Step 6, when I subtract, what if the answer has two digits?DonaganTop AnswererYou would still bring down the next digit from above, and then you would divide the divisor into a threedigit number rather than a twodigit number.

QuestionDo I really need math to survive?DonaganTop AnswererNo, you can usually "survive" just fine without math. Math is critically important, of course, in certain lines of work, and it can make certain personal tasks easier, too. Schools teach math so that their students will have the option of pursuing various highly paid careers in engineering, technology, science, industry and academics.

QuestionCan I still do all this using short division?DonaganTop AnswererShort division is usually performed when the divisor is a onedigit number, but if you're good at mental arithmetic, there's no reason you couldn't use short division with twodigit divisors, too.

QuestionIs singledigit long division like doubledigit long division?DonaganTop AnswererYes, the process is the same in both. Doubledigit just involves a little more work.
Tips
 If you don't want to multiply by hand during the long division, try breaking up the problem into digits and solving each part in your head. For example, 14 x 16 = (14 x 10) + (14 x 6). Write down 14 x 10 = 140 so you don't forget. Then think: 14 x 6 = (10 x 6) + (4 x 6). Well, 10 x 6 = 60 and 4 x 6 = 24. Add 140 + 60 + 24 = 224 and you have the answer.Thanks!
Warnings
 If, at any point, your subtraction results in a negative number, your guess was too high. Erase that entire step and try a smaller guess.Thanks!
 If, at any point, your subtraction results in a number larger than your divisor, your guess wasn't high enough. Erase that entire step and try a larger guess.Thanks!
References
 ↑ http://www.aaamath.com/div4db2r.htm
 ↑ https://www.homeschoolmath.net/teaching/md/two_digit_divisor.php
 ↑ https://study.com/academy/lesson/howtodividebydoubledigitnumbers.html
 ↑ https://www.mathsisfun.com/long_division.html
 ↑ https://sciencing.com/dividethreedigitnumber8298722.html
 ↑ https://www.mathsisfun.com/long_division.html
 ↑ http://www.aaamath.com/div4db2r.htm
 ↑ https://study.com/academy/lesson/howtodividebydoubledigitnumbers.html
 ↑ http://www.math.com/school/subject1/lessons/S1U1L3DP.html
About This Article
To divide by a twodigit number, try to determine whether that number would fit into the first 2 digits of the dividend. If it does, write down how many times it will go into those numbers. Follow the same rules of division that you would with a smaller number. Calculate the remainder, if any, and add the remainder as a prefix to the next number in the dividend. Continue solving the problem to either a whole number with a remainder or a decimal. For tips on estimating the answer, read on!