Chapter 6.4, Problem 17P

Error Analysis In Exercise 16, what kind of errors are likely to occur when solving the problem?

To determine

Find the mistakes that you can commit in the given statements.

Answer to Problem 17P

The mistakes can be :

1. Statement can be misunderstood.
2. Variables can be interchanged.

Explanation of Solution

Given:

One number is 4 less than 3 times the second number.If 3 more than 2 times the first number is decreased by 2 times the second , the result is 11.

Calculation :

Let 1^st number be x

Let 2^nd number be y

Consider the statement :

One number is 4 less than 3 times the second number.

One can make a mistake in subtracting here, misunderstanding the statement.

3 times the second number = 3y

4 less than 3 times the second number = 3y − 4 , some may write it wrong as 4 − 3y

Consider the second statement :

If 3 more than 2 times the first number is decreased by 2 times the second , the result is 11.

This statement might be misunderstood , or the variables may be interchanged, resulting in an error.

3 more than 2 times the first number = 3 + 2x

3 more than 2 times the first number is decreased by 2 times the second = (3 + 2x ) − 2y , some may write it as 2y - (3 + 2x ) .

So, the mistakes can be :

3. Statement can be misunderstood.
4. Variables can be interchanged.