Long Multiplication: 420 × 4

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

What is 420 × 4?

Answer

420 × 4 =
1,680

420 × 4 and 4 × 420 are the same product — the order of the factors never changes the answer, only the working. Below, 420 is multiplied by 4 in a column, digit by digit.

420 × 4 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
×   4
 1680
420 × 4 = 1,680

Step-by-Step Solution

Step 1: Multiply the multiplicand by the last digit of the multiplier, 4: 420 × 4 = 1,680.

  • 0 × 4 = 0. Write 0.
  • 2 × 4 = 8. Write 8.
  • 4 × 4 = 16. Write 6 and carry 1.
  • No digits are left, so the carried 1 is written in front: the partial product is 1,680.

420 × 4

=

1,680

Check It, and What It Is Not

Check by dividing back. Multiplication and division undo each other, so 1,680 ÷ 4 = 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 × 4 is a number, not an area. If those are the sides of a room in feet, the answer is 1,680 square feet — the same arithmetic, a different question, and it is answered by the square footage calculator.

Related Calculations

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 × 4? (The answer is: 1,680). Enter the multiplicand (e.g. '420') and the multiplier (e.g. '4') and hit the button. The order of the two numbers does not matter — 420 × 4 and 4 × 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.
Recalculate with different values ↑

Products of 420

MultiplicationProduct
320 × 41,280
330 × 41,320
340 × 41,360
350 × 41,400
360 × 41,440
370 × 41,480
380 × 41,520
390 × 41,560
400 × 41,600
410 × 41,640
420 × 41,680
430 × 41,720
440 × 41,760
450 × 41,800
460 × 41,840
470 × 41,880
480 × 41,920
490 × 41,960
500 × 42,000
510 × 42,040

FAQ

What is 420 × 4?

420 × 4 = 1,680

Is 420 × 4 the same as 4 × 420?

Yes. Multiplication is commutative, so both come to 1,680. Only the working differs: this page multiplies by 4, which gives a single partial product.

How do you check that 420 × 4 = 1,680?

Divide the product back by one of the factors: 1,680 ÷ 4 = 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 × 4?

There is only one: the multiplier 4 has a single digit, so 420 × 4 = 1,680 is written straight under the line, with no addition step.

See Also