Maria finishes ¾ of the race in 6 hours. How long was the entire race?

We are asked to find the duration of entire race. As Rachel finished of the race in 6 hours, so of x will be equal to 6. Therefore, the duration of entire race was 8 hours.

( i looked this up but that is the answer i dont take any credit for this answer)  

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.

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