Seven /eights each fraction as decimal and as a percent

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?

Whats are the trickiest steps to do when adding or subtracting rational expressions? how does knowledge of rational numbers u in adding and subtracting rational expressions?

Agallon of apple juice cost $7 a pack of eight 4.23oz box of apple juice $2.39 which is a better deal