Help Please! I don't know the answer!

When i add money am i supposed to make it like this 7+12 or 7.00+12.00 because i got 19 dollars for my answer

An episode of a television show is 60 minutes long when it originally airs with commercials. on a dvd without commercials, the episode is only 417 minutes long. how many1-minute commercials did the episode include when it originally aired? write and solve an equation to justify your answer.

What is the unit rate of, 75% high fiber chimp food to 25% high protein chimp food.