Maryland Math 5.NOS.B.7.a

Math5th GradeNumber and Operation Sense

The Standard

5.NOS.B.7: Apply and extend previous understanding of multiplication and division of whole numbers to multiply and divide decimals to hundredths in context.

Apply estimation strategies to estimate products and quotients.

Maryland College and Career Ready Standards for Mathematics (2025) · PERFORM OPERATIONS ON MULTI-DIGIT WHOLE NUMBERS AND WITH DECIMALS TO HUNDREDTHS.

Teacher's field guide

What Students Need to Do: Students round numbers or choose nearby numbers that are easy to work with. They use those numbers to estimate multiplication and division answers, then check whether an exact answer is reasonable.
What Mastery Looks Like: A student sees 4.8 × 19 and uses 5 × 20 to estimate about 100. For 198 ÷ 4, they use 200 ÷ 4 to estimate about 50.
Common Misconceptions: Some students change 198 to 100 just because 100 is easy, making their estimate for 198 ÷ 4 too low. Others treat 4.9 × 20 as 980 because they lose track of the decimal.
How to Assess It: On an exit ticket, ask: Estimate 48.7 × 5.9 and 197 ÷ 4. Write the nearby numbers you used and explain why each answer is reasonable.

Lesson moves

On a 10-by-20 grid, shade 5 rows to model 5 × 20 as an estimate for 4.8 × 19.
Ask, “Is 198 ÷ 4 closer to 25 or 50? What nearby number helps you decide?”
Play Estimate Match with cards showing 4.9 × 21, 198 ÷ 4, and 61 × 29 and cards showing 100, 50, and 1,800.
Post a price tag of $4.80 per notebook and ask students to estimate the cost of 19 notebooks before checkout.

Free download

$Preview of the 5.NOS.B.7.a printable worksheet$

A ready-to-print activity worksheet aligned to 5.NOS.B.7.a, with an answer key for the teacher on its own page. No account needed.

PDF, US Letter, prints cleanly in black and white.

Keep exploring

Grade, subject, topic, and the complete standard are prefilled. Create one free, no account needed.