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The Steps in Double Long Division

"Double division" is a new way to perform long division problems. This new method takes away the guesswork involved in solving long division problems. Instead of using trial and error to figure out which multiple of a divisor goes into the number you are dividing into, you simply choose from a set of numbers created by doubling the divisor three times.
  1. Multiply the Divisor

    • Start by doubling the divisor three times, writing down each number and its multiple on the left-hand column as you go. For example, if you are dividing 5,470 by 22, write down four equations: "1x=22," "2x=44," 4x=88" and "8x=176".

    Find the Largest Multiple

    • Find the largest multiple that will go into the first digits of the number you are dividing into. For example, start with the "54" at the beginning of 5,470. Looking at your list of multiples (22, 44, 88 and 176) and you can see that 44 is the largest multiple that will go into 54.

    Record the Factor

    • Look in the left-hand column to find the factor. You will see that you wrote "2x=44" so you know that the factor of 44 is 2. Write "2" in the right hand column, then add two zeroes after the 2 because you were dividing in the hundreds column. (Add one zero for each digit between the number you divided into, 54 in this case, and the decimal place.) You should have written "200" in the right-hand column.

    Subtract the Multiple

    • Add the same number of zeroes to your multiple, 44 in this case, and subtract it from the number you are dividing into. In this example, you subtract 4,400 from 5,470, to get a result of 1,070.

    Repeat the Steps

    • Start over from Step 2, and find the largest multiple that will go into the first digits. You will write "40" in the right-hand column, because 88 is the largest multiple that will go into 107 (the first three digits of 1,070,) and there is one digit between 107 and the decimal place. Subtract 880 from 1,070, to get a result of 190. Repeat the steps one more time, writing an "8" in the right-hand column because 176 (8x=176) is the largest multiple that will go into 190.

    Find the Remainder

    • When you subtract 176 from 190, you get 14. None of the multiples of 22 will go into 14, so 14 is your remainder.

    Add the Totals

    • Find your answer by adding the totals in the right-hand column. You should have written down "200," "40" and "8" for a total of 248 with a remainder of 14.

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