# math

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mr. Rodriguez, a college instructor, can grade his class papers in 3 hours while it takes his assistant 4 1/2 hours.  If Mr. Rodriguez graded the papers for 1 hour and then left the job for his assistant to complete, how long will it take his assistant to finish grading papers?

• math -

R did 1/3 of the job

So A has to do 2/3 of the job

(2/3) (4 1/2) = (2/3)(9/2) = 3 hours

• math -

1/3+2/9x=1
2/9x=2/3
x=3 hours

• math -

What Damon said

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