Answer:
62 kg.
Explanation:
Let w be the weight of beam and l be the length of beam.
We have been given that the weight that a horizontal beam can support varies inversely as the length of the beam. 
We know that inversely proportion quantities are in form: 
, where k is constant of proportionality.

First of all, we will find the value of k using the 
 and 
 in inversely proportion equation as:



Now we will substitute 
 and 
, in our given equation as:


Therefore, a 10-m beam can support 62 kilograms.