How to calculate 81 multiplied by 21 using long multiplication

How to calculate 81 multiplied by 21

How to calculate 81 multiplied by 21 using long multiplication. Here is step-by-step how to calculate 81 times 21 using long multiplication:

Step 1: Setup
Set up your multiplication problem like this:

	8	1
x	2	1

Step 2: Multiply
1 x 1 = 1. Put 1 below the line and 0 as a reminder on top:

	0
	8	1
x	2	1
		1

Step 3: Multiply
1 x 8 = 8. Take 8 and add 0 from the previous step to get 8. Enter 8 at the bottom:

	8	1
x	2	1
	8	1

Step 4: Add 0
Enter a 0 at the bottom right as a place holder, because you now move over one digit:

	8	1
x	2	1
	8	1
+		0

Step 5: Multiply
2 x 1 = 2. Put 2 below the line and 0 as a reminder on top:

	0
	8	1
x	2	1
	8	1
+	2	0

Step 6: Multiply
2 x 8 = 16. Take 16 and add 0 from the previous step to get 16. Enter 16 at the bottom:

			8	1
x			2	1
			8	1
+	1	6	2	0

Step 7: Add to get answer
Add up the bottom two numbers (81 + 1620 = 1701) to get the answer:

			8	1
x			2	1
			8	1
+	1	6	2	0
=	1	7	0	1

The bottom line is the answer. Therefore, 81 times 21 equals:

1701

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How to calculate 82 multiplied by 21
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