If you have $30 on your debit card can you buy a makeup compact

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?

3/4 = c/36 i need with this fraction proble.

Sylvia rented a boat for $16.50 per hour. her total rental fee was $49.50. for how many hours did sylvia rent the boat