Which one of the following statements expresses a true proportion? a. 54: 9 = 6: 3 b. 2: 1 = 1: 2 c. 3: 4 = 9: 12 d. 7: 9 = 8: 9

The answer is d, because 3: 4 is the same as 9: 12. if you multiply 3 and 4 by 3, you get 9 and 12 respectively. therefore, 3: 4 is the same as 9: 12, a true proportion.

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