Grade 5Math

Choosing Efficient Partial Quotients

When using the partial quotients division method, students should choose larger, friendlier numbers (like multiples of 10 or 100) as partial quotients to solve problems in fewer steps with less chance for error, as covered in Illustrative Mathematics Grade 5, Chapter 4: Wrapping Up Multiplication and Division with Multi-Digit Numbers. For example, when dividing 756 by 6, choosing 100 as the first partial quotient (6 x 100 = 600) is more efficient than choosing 10.

Key Concepts

When using the partial quotients method, choose numbers that are easy to multiply by the divisor, like multiples of 10 or 100. These "friendly numbers" help you solve the problem in fewer, simpler steps.

Common Questions

What is the partial quotients method?

The partial quotients method is a division strategy where you subtract multiples of the divisor from the dividend in steps (chunks), recording each quotient, until you reach zero or a remainder.

How do you choose efficient partial quotients?

Choose multiples of 10 or 100 that are easy to multiply by the divisor; larger partial quotients remove bigger chunks from the dividend at once, meaning fewer steps to complete the problem.

Why is choosing 100 better than choosing 10 when dividing 756 by 6?

Choosing 100 (6 x 100 = 600) removes 600 from 756 in one step, leaving only 156; choosing 10 repeatedly requires many more steps and increases the chance of arithmetic errors.

Can you get the same answer with less efficient partial quotients?

Yes, you get the same correct answer regardless of which partial quotients you choose, but less efficient choices require more steps, more calculations, and more opportunity for mistakes.

What makes a partial quotient friendly?

Friendly partial quotients are multiples of powers of 10 (10, 20, 50, 100) that are easy to multiply mentally and that remove large portions of the dividend efficiently.