Chapter 1.7, Problem 36P

Use mental math to find each product.

$6\times 397$

To determine

To find the product:

  $6\times 397$

Answer to Problem 36P

2382

Explanation of Solution

Given:

  $6\times 397$

Concept Used:

Commutative property of multiplication: $a\times b=b\times a$

Calculation:

In order to find the product:

  $6\times 397$

First, use commutating property of multiplication, as

  $6\times 397=397\times 6$

Now, multiply the factor(397) digit by digit with 6, and keep writing down the carry to add also. This is done as:

  $\begin{array}{l}397\times 6=\stackrel{5}{3}\stackrel{4}{9}7\\ \underset{\_}{\times 6}\\ \text{ 2382}\end{array}$

Thus,

  $6\times 397=2382$