9/5+2/8 adding with unlike denominators

Christina can paint 420 square feet in 105 minutes. which unit rate describes the scenario?

Four individuals pool money together to start a new business and agree to split the profits equally. n invests $6,000, x invests $2,000, y invests $8,000 and z invests $4,000. if the profits for the first month were $100,000, y receives than if the profits were divided in proportion to how much they invested.

1) you deposit $2,500 in an account that earns 4% simple interest. how much do you earn in eight years?