Chapter A.1, Problem 144AYU

To determine

To show:

a. Voltage of 214 volts is acceptable.

Answer to Problem 144AYU

a. $6\le 8$

Explanation of Solution

Given:

In other countries, normal household voltage is 220 volts. It is acceptable for the actual voltage $x$ to differ from normal by at most 8 volts. A formula that describes this is $\left|x-220\right|\le 8$.

Calculation:

$\left|x-220\right|\le 8$

a. $\left|214-220\right|\le 8$

$\left|-6\right|\le 8$

$6\le 8$

Voltage of 214 volts is acceptable.

To determine

To show:

b. Voltage of 209 volts is not acceptable.

Answer to Problem 144AYU

b. $11>8$

Explanation of Solution

Given:

In other countries, normal household voltage is 220 volts. It is acceptable for the actual voltage $x$ to differ from normal by at most 8 volts. A formula that describes this is $\left|x-220\right|\le 8$.

Calculation:

$\left|x-220\right|\le 8$

b. $\left|209-220\right|\le 8$

$\left|-11\right|\le 8$

$11\nleqq 8$

$11>8$

Voltage of 209 volts is not acceptable.