Long Multiplication: 420 × 8

Long Multiplication Calculator
Multiplicand (number to be multiplied)
Multiplier (number to multiply by)

What is 420 × 8?

Answer

420 × 8 =
3,360

420 × 8 and 8 × 420 are the same product — the order of the factors never changes the answer, only the working. Below, 420 is multiplied by 8 in a column, digit by digit.

420 × 8 in a Column

The multiplicand goes on top, the multiplier underneath, both aligned on the right. The multiplier has a single digit, so there is one partial product and the answer goes straight under the line.

  420
×   8
 3360
420 × 8 = 3,360

Step-by-Step Solution

Step 1: Multiply the multiplicand by the last digit of the multiplier, 8: 420 × 8 = 3,360.

  • 0 × 8 = 0. Write 0.
  • 2 × 8 = 16. Write 6 and carry 1.
  • 4 × 8 = 32, plus the carried 1 makes 33. Write 3 and carry 3.
  • No digits are left, so the carried 3 is written in front: the partial product is 3,360.

420 × 8

=

3,360

Check It, and What It Is Not

Check by dividing back. Multiplication and division undo each other, so 3,360 ÷ 8 = 420 must come out exactly, with no remainder.

Fractions are a different calculation. Both factors here are whole numbers; for 2/3 or 2 3/4 use the fraction multiplication calculator, which multiplies numerators and denominators separately.

420 × 8 is a number, not an area. If those are the sides of a room in feet, the answer is 3,360 square feet — the same arithmetic, a different question, and it is answered by the square footage calculator.

See Also

Long Multiplication Calculator

This calculator multiplies two whole numbers the way it is done on paper: digit by digit, carrying where the column overflows, then adding the partial products together. For example, it can help you find out what is 420 × 8? (The answer is: 3,360). Enter the multiplicand (e.g. '420') and the multiplier (e.g. '8') and hit the button. The order of the two numbers does not matter — 420 × 8 and 8 × 420 are the same product — so either number can go on top. Fractions and mixed numbers belong to the fraction multiplication calculator, and the reverse operation is long division.

Products of 420

MultiplicationProduct
320 × 82,560
330 × 82,640
340 × 82,720
350 × 82,800
360 × 82,880
370 × 82,960
380 × 83,040
390 × 83,120
400 × 83,200
410 × 83,280
420 × 83,360
430 × 83,440
440 × 83,520
450 × 83,600
460 × 83,680
470 × 83,760
480 × 83,840
490 × 83,920
500 × 84,000
510 × 84,080

FAQ

What is 420 × 8?

420 × 8 = 3,360

Is 420 × 8 the same as 8 × 420?

Yes. Multiplication is commutative, so both come to 3,360. Only the working differs: this page multiplies by 8, which gives a single partial product.

How do you check that 420 × 8 = 3,360?

Divide the product back by one of the factors: 3,360 ÷ 8 = 420 exactly, with no remainder. Multiplication and division undo each other, which is what makes this check work.

What are the partial products of 420 × 8?

There is only one: the multiplier 8 has a single digit, so 420 × 8 = 3,360 is written straight under the line, with no addition step.