A bicycle is traveling at 20 feet per minute. What is the bicycle's speed expressed in inches per second?
To convert from feet per minute to inches per second, I need to multiply by two conversion factors: one that changes feet to inches, and one that changes minutes to seconds. There are 12 inches in one foot, so to change feet to inches, I need to multiply by 12. This will make the units cancel out, leaving me with inches per minute. This will also make the units cancel out, leaving me with inches per second. So, the final conversion is: 20 feet per minute times 12 inches per foot divided by 60 seconds per minute. I can simplify this expression by canceling out the common factors of 12 and 60. 12 and 60 have a greatest common factor of 12, so I can divide both by 12 to get 1 and 5. This leaves me with: 20 times 1 inch per 5 seconds, or 4 inches per second. Therefore, the bicycle's speed is 4 inches per second. 