How do I explain how 5 yards in feet is 15 yards?

Moira has a canvas that is 8 inches by 10 inches. she wants to paint a line diagonally from the top left corner to the bottom right corner. approximately how long will the diagonal line be?

For every touchdown scored by the timberwolves the mascot does three backflips if the cheerleaders set off six confetti cannons how many touchdowns did the timberwolves score if the cheerleader set of 18 confetti cannons

Me answer this question: -2/3p + 1/5 - 1 + 5/6p i think the simplified expression is 1/6p - 4/5 correct me if i'm wrong, and explain it! if i have it right, just tell me. you so