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How Do You Estimate a Quotient Using Compatible Numbers?

Estimate the quotient of 55,304 ÷ 875 by using compatible numbers.

Summary

  1. Compatible numbers are numbers that are close to the numbers they're replacing that divide evenly into each other
  2. The quotient is the result you get when you divide
  3. 56,000 is pretty close to 55,304
  4. 800 is pretty close to 875, AND it divides evenly into 56,000
  5. Divide the non-zero parts of each number, 56÷8, to get the first part of the estimate
  6. Then add on however many zeros were left in the problem to get your estimate
  7. In this case, we had one zero left so the estimate is 70

Notes

    1. Compatible numbers are numbers that are close to the numbers they're replacing that divide evenly into each other
    1. When we estimate we're trying to make the problem easier, so we can solve it without doing calculations
    2. Dividing is easier when we have numbers that divide evenly into each other, so that's how we'll estimate
    1. 56,000 is like 560 times 100
    2. 800 is like 8 times 100
    3. When we divide 56,000 by 800, we can cancel out the 100's, and we're left with 560 divided by 8
    4. In other words, since there are two zeroes in the divisor, we cancel out two zeros in the dividend
    1. Since we rounded the dividend and divisor into such nice numbers, we can easily divide the front digits to get a round number!
    1. Since we canceled a few zeroes, there's only one zero left
    1. There are usually more than just one pair of compatible numbers to choose from
    2. As long as the numbers are easily divisible and close to the original numbers, they'll be good compatible numbers!
    3. We'll get a slightly different answer, but it's still a good estimate of our quotient