From the information provided, Tom's actual height is 68 inches while his head measures 9.1 inches.
The proportion of his head to his height therefore is;
The action figure measures 15 centimeters. Uing the standard rate of conversion (centimeters to inches) we would have;
Note that the centimeter measure is divided by 2.54 to get the equivalent in inches.
Now that we've derived the height of the action figure to be 5.9 inches, the proportion to calculate the action figure's head shall be;
ANSWER:
The action figure's head measures 0.79 inches