Long Multiplication: 78 × 2
What is 78 × 2?
Answer
78 × 2 and 2 × 78 are the same product — the order of the factors never changes the answer, only the working. Below, 78 is multiplied by 2 in a column, digit by digit.
78 × 2 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.
| 7 | 8 | ||
| × | 2 | ||
| 1 | 5 | 6 |
Step-by-Step Solution
Step 1: Multiply the multiplicand by the last digit of the multiplier, 2: 78 × 2 = 156.
- 8 × 2 = 16. Write 6 and carry 1.
- 7 × 2 = 14, plus the carried 1 makes 15. Write 5 and carry 1.
- No digits are left, so the carried 1 is written in front: the partial product is 156.
78 × 2
=156
Check It, and What It Is Not
Check by dividing back. Multiplication and division undo each other, so 156 ÷ 2 = 78 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.
78 × 2 is a number, not an area. If those are the sides of a room in feet, the answer is 156 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
<a href="https://calculat.io/en/number/long-multiplication/78--2">78 × 2 = 156 - Long Multiplication - Calculatio</a>