A bird flies from the bottom of a canyon that is 51 3/10 feet below sea level to a nest that is 737 1/10 feet above sea level.

The bird would have to fly up 685.8 feet up.

Step-by-step explanation

If we are talking about how much the bird wants to fly up to the nest, then it would be 685.8 ft up.

first,

you take the fractions which are (-51 3/10) and (737 1/10)

Then we make them decimals to be easier (on my pov) Then we have

-51.3 and +737.1

Next we add 737.1+(-51.3)

which equals 685.8 feet.