Multiply each place, starting with the ones, and carry to the next place. For two digits by two, make one row for the ones and one for the tens, then add the rows.
partial productthe answer for one part of a multiplication
regroupcarry tens to the next place
factora number being multiplied
productthe answer to ×
Watch for: Adding the carried digit before multiplying instead of after. Leaving out the 0 in the second row when multiplying by the tens digit. An answer far from a quick estimate, like 631 × 4 nowhere near 2,400.
At home: Estimate first: 631 × 4 is about 600 × 4 = 2,400. If the answer is far from that, look again.
Sample sheet and answer key
Luna's Space Adventure
Grade 4 · Multiplying bigger numbers · 4.NBT.B.5
NameDate
Astronaut Luna is exploring a far-off corner of space. Solve each problem to help Luna's mission go smoothly!
By one digit
Multiply each place; carry as you go.
1
531×4
2
302×6
3
682×9
4
770×5
Two digits by two digits
Two rows of partial products, then add.
1
70×40
2
32×52
Riddle time
Solve each one, then use the code to answer the riddle.
New problems every time, three levels (gentle, core and stretch), themes to pick from, a second page if you want one. Each sheet comes with an answer key and a one-page guide for grown-ups.
