No they are not, 6/8 could also be represented as 3/4. Therefore they are not equivalent. You would divide each side by the factor they have in common such as 2.
Volume is cubed. If the dimensions are doubled, cube the scale factor:
2^3 = 8
The volume will increase by a scale of 8.
The new volume would be 97 x 8 = 776 ft^3
The answer would be 6x/5-16/5
