Question 105135
Let the smallest pipe length = L
The length of middle pipe = "the middle piece should be twice the length of the smallest piece" = 2L
And Length of Largest Pipe = "The largest piece should be twice the length of the middle piece" = 2 x 2L = 4L

Now total length of 3pieces = L + 2L + 4L = 7L
But we know that total length = 24

Therefore 7L = 24
or L = 24/7 which is the length of the smallest pipe

Can you find out the length of the remaining pieces?