Final answer:
Duane's pencil, at 70 millimeters, is longer than Fred's pencil, which is 64 millimeters. Duane's pencil is 6 millimeters longer.
Step-by-step explanation:
To determine whose pencil is longer between Duane and Fred, we need to compare the lengths of their pencils using the same unit of measurement. Duane has a pencil that is 7 centimeters long, and Fred has a pencil that is 64 millimeters long. To compare them, it's easiest to convert either centimeters to millimeters or millimeters to centimeters. Since 1 centimeter is equal to 10 millimeters, we can convert Duane's pencil length to millimeters:
Duane's pencil: 7 cm × 10 = 70 mm
Now we can compare the lengths:
70 mm (Duane's pencil) > 64 mm (Fred's pencil)
Therefore, Duane's pencil is longer than Fred's pencil by:
70 mm - 64 mm = 6 mm
So, Duane's pencil is 6 millimeters longer than Fred's.