SME
Grade 3 Math · Problem type
Multiply in any order
Use this for 4 × 7 = 7 × 4: turn the array to use a fact you know.
Diagram
4 rows of 7 = 7 rows of 4: 4 × 7 = 7 × 4 = 28
This is an example. Type your own values to start a new problem.
Rows
×
In each row
=
In each row
×
Rows
=
Total
Formulas
4 × 7 = 28
Rows × in each row = total
7 × 4 = 28
In each row × rows = total
Assumptions
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Turning an array changes rows into columns, not the total.
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So 4 × 7 = 7 × 4: use the fact you know.
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Any number times 1 is that number. Any number times 0 is 0.
Step-by-step
WE KNOW
Rows: 4
In each row: 7
FIND
total
Step 1 · Find total
4 × 7 = ?
Rows × in each row = total
Multiply the rows by the number in each row.
4 × 7 = 7 × 4. Use the fact you know.
5 × 4 = 20 and 2 × 4 = 8
20 + 8 = 28
Total = 28
Check
Put the numbers back in. Both sides should match.
4 × 7 = 28 ✓
7 × 4 = 28 ✓
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.