Working together, rocco and giulia can paint a room in 3 hours. it would have taken rocco 7 hours to do the job alone. which equation can be used to determine r, giulia’s rate of work in parts per hour? a- 3/7+3r=7 b- 3/7 + 3r =1 c- 1/7 = r d- 3/7 = 3r

B

Step-by-step explanation:

Rocco: of the job per hour

Giulia: of the job per hour

Together: of the job per hour

Rocco + Giulia = Together

+ =

+ =

3x + 21 = 7x

       21 = 4x

It will take Giulia hours to paint the room by herself.

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Giulia: =

A)

    1 = 7

    FALSE

B)    

    1 = 1

    TRUE

answer:   2 multiplied by x =24

step-by-step explanation:

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.