C Challenge

51. Chemistry Matter is in a liquid state when its temperature is between its melting point and its boiling point. The melting point of the element mercury is − 38.87 ° C , negative , 38.87 , degrees cap c comma  and its boiling point is 356.58°C. What is the range of temperatures in degrees Fahrenheit for which mercury is not in a liquid state? (Hint: C = 5 9 ( F − 32 ) c equals , 5 ninths . open , f minus 32 , close ) Express the range as an inequality and in interval notation.
52. Heart Rates Recommended heart rates during exercise vary with age and physical condition. For a healthy person doing moderate to intense exercise, such as hiking, the inequality 0.5 ( 220 − a ) ≤ R ≤ 0.9 ( 220 − a ) 0.5 open 220 minus eh close less than or equal to r less than or equal to 0.9 open 220 minus eh close  gives a target range for the heart rate R (in beats per minute), based on age a (in years).
    1. What is the target range for heart rates for a person 15 years old?
    2. How old is a person whose target range is between 99 and 178.2 beats per minute?

Standardized Test Prep

SAT/ACT

53. A taxi traveled 5 mi to John's home and then drove him to the airport 10 mi away. Which inequality represents the possible distances d of the taxi from the airport when it started traveling toward John's home?
    1. 5 ≤ d ≤ 10 5 less than or equal to d less than or equal to 10
    2. 5 ≤ d ≤ 15 5 less than or equal to d less than or equal to 15
    3. 0 ≤ d ≤ 5 0 less than or equal to d less than or equal to 5
    4. 0 ≤ d ≤ 10 0 less than or equal to d less than or equal to 10
54. A student must earn at least 24 credits in high school in order to graduate. Which inequality or graph does NOT describe this situation?
    6. c ≤ 24 c less than or equal to 24
    7. c ≥ 24 c greater than or equal to 24
    8. 24 ≤ c 24 less than or equal to c
    9. 

Short Response

55. The County Water Department charges a monthly administration fee of $10.40 plus $.0059 for each gallon of water used, up to, but not including, 7500 gal. What is the minimum and maximum number of gallons of water used by customers whose monthly charge is at least $35 but no more than $50? Express amounts to the nearest gallon.

Mixed Review

See Lesson 3-5.

Let A = {1, 3, 5, 7}, let B = {4, 8, 12}, and let the universal set be U = {1, 2, 3, 4, 5, 7, 8, 12, 15}.

56. What are the subsets of A?
57. What is B'?
58. Is B' a subset of A?

See Lesson 3-4.

Solve each inequality.

59. 5 < 6 b + 3 5 less than 6 b plus 3
60. 12 n ≤ 3 n + 27 12 n less than or equal to 3 n plus 27
61. 2 + 4 r ≥ 5 ( r − 1 ) 2 plus 4 r greater than or equal to 5 open r minus 1 close

Get Ready! To prepare for Lesson 3-7, do Exercises 62–64.

See Lesson 1-5.

Complete each statement with < , = , less than comma equals comma  or > . greater than .

62. | 3 − 7 | absolute value of 3 minus 7 , end absolute value ,  _____ 4
63. | − 5 | absolute value of negative 5 , end absolute value ,  + 2 _____6
64. | 6 − 2 1 4 |   _ 3 5 8 absolute value of . 6 minus 2 , and 1 fourth , end absolute value , . modified with under bar below , 3 , and 5 eighths

Table of Contents