17) \( 4 \mathrm{ft} 11 \mathrm{in}=\ldots \) 19) \( 5 \mathrm{ft} 8 \mathrm{in}=\ldots \) in 21) \( 91 \mathrm{in}=\ldots \mathrm{ft} \)

Did you know that the foot was originally based on the length of the human foot? In ancient times, kings and rulers would use their own feet as a standard measure, which led to varying interpretations of a "foot" throughout different cultures. The length we know today, 12 inches, was standardized in the 12th century under King Henry I of England! When converting feet and inches, it can be easy to mix up the units—especially if you're doing multiple conversions! A helpful tip is to always convert the inches to feet first. For instance, remember that there are 12 inches in a foot; so for “4 ft 11 in,” simply think of it as “4 ft + 11/12 ft” to get your total. And don't forget to double-check your math to avoid small mistakes that can snowball into bigger errors!