Austin is on his way home in his car. his drive is 30 miles long. he has finished five-sixths of the drive so far. how far has he driven?

30 miles is two-thirds of x (where x is the total distance) 

30 = (2/3)*x 

30*3 = 2x 
90 = 2x 

90/2 = x 

45 = x 

x = 45 

The total length of his drive is 45 miles

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm