College Algebra Final Review

1.  How many gallons of a 35% brine solution must be mixed with 12 gal of a 55% brine solution in order to get a 45% solution?

• 12 gallons
• 6 gallons
• 6.8 gallons
• 8 gallons

1.  As a nasal decongestant, doctors sometimes prescribe saline solutions with a concentration between 6% and 20%.  In “the old days”, pharmacists had to create different mixtures, but only needed to stock these concentrations, since any percentage in between could be obtained using a mixture.  An order comes in for 50 milliliter (mL) of a 15% solution.  How much of each should be used?

• 17.9 ml of 20%
  32.1 ml 6%
• 17.9 ml of 6%
  32.1 ml 20%
• 22.5 ml of 6%
  27.5 ml of 20%
• 22.5 ml of 20%
  27.5 ml of 6%

1.  Determine the domain of  y = 2x + 3

• (-2/3, 2/3)
• x > 2/3
• x<2/3
• all real numbers

1.   The height of an object thrown upward from the roof of a building 408 ft tall, with an initial velocity of 96 ft/sec, is given by the equation h = -16t² + 96t + 408, where h represents the height of the object after t seconds.  How long will it take the object to hit the ground?  Answer in exact form and decimal form rounded to the nearest thousandth.

• 2.874 seconds
• 8.874 seconds
• No solution

1.  The height of an object thrown upward from the floor of a canyon 106 ft deep, with an initial velocity of 120 ft/sec, is given by the equation h = -16t² + 120t  - 106, where h represents the height of the object after t seconds.  How long will it take the object to rise to the height of the canyon wall?  Answer in exact form and decimal form rounded to hundredths. 

• 1.02 seconds
• 6.48 seconds
• -1.02 seconds
• -6.48seconds

 A batter has just flied out to the catcher, who catches the ball while standing on home plate.  If the batter made contact with the ball at a height of 4 ft and the ball left the bat with an initial velocity of 128 ft/sec, how long will it take the ball to reach a height of 116 ft?  

• 1 second
• 8 seconds
• 3 seconds
• 7 seconds

 A batter has just flied out to the catcher, who catches the ball while standing on home plate.  If the batter made contact with the ball at a height of 4 ft and the ball left the bat with an initial velocity of 128 ft/sec, how high is the ball 5 seconds after contact? 

• 244 feet
• 124 feet

1.   A batter has just flied out to the catcher, who catches the ball while standing on home plate.  If the batter made contact with the ball at a height of 4 ft and the ball left the bat with an initial velocity of 128 ft/sec,  the catcher catches the ball at a height of 4 ft, how long was it airborne?

• 1 second
• 8 seconds
• 3 seconds
• 7 seconds