Mystery Bureau › Grade 4 standards › 4.NBT.B.5
📘 Common Core · 4.NBT.B.5 · Grade 4
The second half of this standard is the part that gets skipped: illustrate and explain the calculation using equations, arrays, or area models. Fourth grade is meant to understand why partial products work, not only to execute them. A student who can compute 38 × 3 but cannot say why it equals 90 plus 24 has met half of it.
Quoted verbatim from the Common Core State Standards for Mathematics. Nothing here is paraphrased.
| 4.NBT.B.5 | Multiply a whole number of up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models. |
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In plain English: Multiply up to a four-digit number by a one-digit number, and two two-digit numbers, using place value and the properties of operations.
Each one runs in the browser with no account and nothing stored. Five questions apiece.
Real output from the activities above — not written for this page, drawn from the same pools a student gets. The numbers are rebuilt on every attempt.
| 35 × 3 = ? | 105 |
| 23 × 7 = ? | 161 |
| 20 × 7 = ? | 140 |
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