What does growth mean in math

Negative 5 1/12 + negative 4 1/4 + 6 3/4

Emily is entering a bicycle race for charity. her mother pledges $0.90 for every 0.75 mile she bikes. if emily bikes 18 miles, how much will her mother donate?

Ten members of balin's soccer team ran warm ups for practice. each member ran the same distance. their combined distance was 5/6 of a mile. to find the distance that each member ran, balin wrote the expression below.