To find the number of marbles \( m \) in the bag, you can set up the following equation based on the information provided:
\[ m = 6 \times 13 \]
In this equation, \( 6 \) is the number of players and \( 13 \) is the number of marbles each player receives.
Now, let's solve for \( m \):
\[ m = 6 \times 13 \]
Calculating that gives:
\[ m = 78 \]
Therefore, there are 78 marbles in the bag.