Reasonableness of Division Quotients

This lesson teaches how to assess the reasonableness of division quotients using compatible numbers. It explains the concept through examples, showing how to adjust multi-digit dividends to match the divisor's multiples, making it easier to estimate the quotient. The lesson includes two examples: Danielle's division of 413 by 7, which is found unreasonable, and Tracy's division of 5625 by 9, which is reasonable. By the end, students learn to use compatible numbers to check if division results are sensible.

What is one method to check the reasonableness of a division answer?

• Estimate using compatible numbers

• Recalculate the problem

• Ask a friend

• Use a calculator

Why is Danielle's answer of 89 not reasonable when dividing 413 by 7?

• Because 413 is a prime number

• Because the expected quotient is closer to 60

• Because 413 is not divisible by 7

• Because 89 is a prime number

What is the purpose of listing multiples of the divisor in Danielle's problem?

• To simplify the division process

• To check for errors in calculation

• To identify compatible numbers

• To find the exact quotient

How do you make a number compatible with a divisor?

• By dividing the number by the divisor

• By adjusting the number to the nearest multiple of the divisor

• By subtracting the divisor from the number

• By adding the divisor to the number

What was Tracy's original division problem?

• 5625 divided by 9

• 5400 divided by 9

• 413 divided by 7

• 420 divided by 7

Why was Tracy's answer of 625 considered reasonable?

• Because it was exactly correct

• Because it was close to the expected quotient of 600

• Because it was a multiple of 9

• Because it was a round number

What is the first step in assessing the reasonableness of a quotient using compatible numbers?

• Divide the numbers directly

• Subtract the divisor from the dividend

• Add the numbers together

• List the multiples of the divisor

What is the compatible number for 5625 when using 9 as the divisor?

• 5400

• 5600

• 5300

• 5500

What is the expected quotient when dividing 5400 by 9?

• 600

• 675

• 650

• 625

What did you learn in this lesson about using compatible numbers?

• How to subtract numbers

• How to multiply numbers

• How to assess the reasonableness of quotients

• How to add numbers