Box multiplication
keynotes :
Box method of multiplication:
Step 1: Make a table with the place values of the first factor along the top and the place values of the second factor down the left.
Step 2: Multiply the place values and enter their products in the table.
Step 3: Sum each row of the table.
Step 4: Add these row sums. This is the product of the original factors.
Learn with an example
😀 Use the box method to find 87×15.
Calculate the sums on the right. Add these sums to find 87×15.
87×15 = ?,???
Step 1
To multiply two numbers using the box method, make a table with the place values of the first factor along the top and the place values of the second factor down the left.
Step 2
Multiply the place values and enter their products in the table.
Simplify the table.
Step 3
Sum each row of the table.
Step 4
Add these row sums. This is the product of the original factors.
870 + 435 = 1,305
So, 87 × 15 = 1,305.
😀 Use the box method to find 38×50.
Calculate the sums on the right. Add these sums to find 38×50.
38×50 = ?,???
Step 1
To multiply two numbers using the box method, make a table with the place values of the first factor along the top and the place values of the second factor down the left.
Step 2
Multiply the place values and enter their products in the table.
Simplify the table.
Step 3
Sum each row of the table.
Step 4
Add these row sums. This is the product of the original factors.
1,900+0=1,900
So, 38×50=1,900.
😀 Use the box method to find 81×83.
Calculate the sums on the right. Add these sums to find 81×83.
81×83 = ?,???
Step 1
To multiply two numbers using the box method, make a table with the place values of the first factor along the top and the place values of the second factor down the left.
Step 2
Multiply the place values and enter their products in the table.
Simplify the table.
Step 3
Sum each row of the table.
Step 4
Add these row sums. This is the product of the original factors.
6,480+243=6,723
So, 81×83=6,723.
Let’s practice!
