Math question on Inequalities

Test Preparation SAT Preparation
1

<p>A regulation for riding a certain amusement park ride requires that a child be between 30 inches and 50 inches tall. Which of the following inequalities can be used to determine whether or not a child’s height h satisfies the regulations for this ride?</p>

<p>A. |h – 10| < 50
B. |h – 20| < 40
C. |h – 30| < 20
D. |h – 40| < 10
E. |h – 45| < 5</p>

<p>The only way I can think of is to rely on the concept of absolute value - the distance from midpoint cannot be more than 10. Is there any other way of looking at this problem?</p>

2

<p>The correct answer is “D” because the absolute value will make each inequality become two inequalities:
lh-40l <10 is </p>

<p>h-40<10
h-40>-10</p>

<p>add 40 to both sides and you get </p>

<p>h<50
and
h>30</p>