Chapter 8.4, Problem 56PPS

To determine

The number of inches in 200 miles.

Answer to Problem 56PPS

  $\text{4inches}$

Explanation of Solution

Given:

A scale of $150\text{miles=}3\text{inches}$ .

Concept Used:

Rules of Addition/ Subtraction:

• Two numbers with similar sign always get added and the resulting number will carry the similar sign.
• Two numbers with opposite signs always get subtracted and the resulting number will carry the sign of larger number.

Rules of Multiplication/ Division:

• The product/quotient of two similar sign numbers is always positive.
• The product/quotient of two numbers with opposite signs is always negative.

Calculation:

In order to find how many inches represents $150\text{miles=}3\text{inches}$ , use the unitary method with the given scale and simplify further as shown below,

  $\begin{array}{c}150\text{miles=}3\text{inches}\\ \text{1}\text{miles}=\frac{3}{150}\text{inches}\\ \text{So,}\\ 200\text{miles}=\frac{3}{150}\times 200\text{inches}\\ \text{=4inches}\end{array}$

Thus The number of inches is $\text{4inches}$ .