10-7 Using Rational Equations Standard 15.0: Apply algebraic techniques to rate and work problems.
Vocabulary Problem-Solving Guidelines UNDERSTAND the problem Develop and carry out a PLAN Find the ANSWER and CHECK
#1 Solving Work Problems A contractor finds that it takes Crew A 6 hours to construct a wall of a certain size. Crew B takes 8 hours to construct a wall of the same size. How long will it take if they work together? Let x = the total number of hours to complete the job.
#1 Solving Work Problems Working Together
#1 Solving Work Problems
#2 Solving Motion Problems One boat travels 10 km/h faster than another. While one boat travels 120 km, the other travels 155 km. Find their speeds. Let t = time each boat traveled.
#2 Solving Motion Problems Distance Rate Time SlowBoat 120 r t Fast Boat 155 r + 10 t Solve both equations for t
#2 Solving Motion Problems Substitute the first equation for t
#3 Solving Number Problems The reciprocal of two more than a number is three times the reciprocal of the number. Find the number.
#3 Solving Number Problems