- Concept Videos
- Solutions 34

Convert:

b. 116 ft to cm

Hey guys, in this video we're going to continue with our discussion of unit conversions so here they give us 116 feet and they ask to change it into centimeters so the conversion factors that we need to recall here is remember we've seen centimeters before we relate them to inches so 1 inch is equal to 2.54 cm and we already know there's a connection between feet and inches 1 foot = 12 inches so what does that mean? That means that our roadmap to get to the correct answer is feet to inches to centimeters, so we want to get rid of the feet so we're going to start with 116 feet we want to get rid of feet so feet go on the bottom. Here we're going to change feet into inches remember that 1 foot is equal to 12 inches then we want to get rid of inches so inches go on the bottom we want centimeters so centimeters goes on top, 1 inch is equal to 2.54 centimeters so inches cancel out and now I'm going to have centimeters at the end so here when we work this out in our calculator we get 3535.68 centimeters. Oh, we can't just stop there if you want the answer to the correct number of significant figures 116 has 3 sig figs so I want 3 digits here, next to this 3 is a 5 which means I'm going to round the 3 up to a 4, here we want 3 six figs so we're going to have to change it to scientific notation so that's going to be 3.54x10^3 centimeters so this will be our correct answer with the correct number of significant figures.