If you’re looking for the answer, Fourth Class can tell you!
First, it is important to choose a lever and a fulcrum. We used a ruler (lever) and a pencil (fulcrum). In order to balance it we found its centre of gravity. We then tried balancing the lever using coins on either side. We found out that two of the same coins must be at the same distance on each end of the ruler in order for the lever to balance.
Take a look at our results: