Answer:
22 chocolates
Explanation:
First, let x represent the number of chocolates Mary has. Since she always has 2 extra chocolates, the number of chocolates distributed to her friends would be x - 2. And x - 2 is the least common multiple of 4 and 5 because x - 2 chocolates are evenly distributed among 4 and 5 friends. The LCM of 4 and 5 is 20, so x - 2 is 20. Mary has 22 chocolates.