Long Multiplication: 420 × 3
What is 420 × 3?
Answer
420 × 3 and 3 × 420 are the same product — the order of the factors never changes the answer, only the working. Below, 420 is multiplied by 3 in a column, digit by digit.
420 × 3 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.
| 4 | 2 | 0 | ||
| × | 3 | |||
| 1 | 2 | 6 | 0 |
Step-by-Step Solution
Step 1: Multiply the multiplicand by the last digit of the multiplier, 3: 420 × 3 = 1,260.
- 0 × 3 = 0. Write 0.
- 2 × 3 = 6. Write 6.
- 4 × 3 = 12. Write 2 and carry 1.
- No digits are left, so the carried 1 is written in front: the partial product is 1,260.
420 × 3
=1,260
Check It, and What It Is Not
Check by dividing back. Multiplication and division undo each other, so 1,260 ÷ 3 = 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 × 3 is a number, not an area. If those are the sides of a room in feet, the answer is 1,260 square feet — the same arithmetic, a different question, and it is answered by the square footage calculator.
Related Calculations
See Also
- Long Division Calculator - Step-by-step long division with detailed explanation
- Multiplying Fractions Calculator - Multiply fractions, mixed numbers and whole numbers step by step
- Factors of a Number - List all Factors and Factor Pairs of a Number
- Greatest Common Factor - Find the Greatest Common Factor (GCF) of two numbers
- Least Common Multiple - Find the Least Common Multiple (LCM) of two numbers
