Can I get help with this?

How many zeroes are at the end of $42! + 10!$ ($42$ factorial plus $10$ factorial)? (Reminder: The number $n!$ is the product of the integers from $1$ to $n$. For example, $5!=5\cdot 4\cdot3\cdot2\cdot 1= 120$.)

sandwich Aug 3, 2023