Chapter 1.1, Problem 25P

Error Analysis A student writes $5y\cdot 3$ to model the relationship the sum of 5y and 3. Explain the error.

To determine

To find: the error in writing algebraic expression for phrase “the sum of $5y$ and 3” as $5y\cdot 3$ .

Answer to Problem 25P

Error is that $5y\cdot 3$ represents the product of $5y$ and 3 not their sum.

Explanation of Solution

Given:

The phrase “the sum of $5y$ and 3”

Error here is that $5y\cdot 3$ represents the product of $5y$ and 3 not their sum.

The symbol for sum is ‘ $+$ ’

So, the phrase “the sum of $5y$ and 3” can be translated as:

  $5y+3$