Three tennis balls have the same mass. If the total mass of the 3 balls is 6 3/10 grams, what is the mass of 1 ball

To find the mass of one ball, we need to divide the total mass of the three balls by the number of balls.

The total mass of the three balls is 6 3/10 grams.
Converting the mixed number to an improper fraction: 6 3/10 = 63/10 grams.
Dividing the total mass by the number of balls: (63/10) grams / 3 = 21/10 grams.

Therefore, the mass of one ball is 21/10 grams.