Terry from Warren Comprehensive School sent
us his solution to this problem:

The Red rod is $\frac{1}{4}$ of the Brown rod.

The Green rod is $\frac{2}{3}$ of the Blue rod.

The Pink rod is $\frac{2}{5}$ of the Orange rod.

The Green rod is $\frac{3}{10}$ of the Orange rod.

The method for working out the short rod as a fraction of the
long rod is:

When you complete the rows of rods so that they match, the
number of long rods is the numerator for the fraction and the
number of short rods is the denominator for the fraction.

It is easy to see why this works when you use only one long rod - you can return to the interactivity to see why this works in general.

Well done Terry.