Question

Carl can paint a house in 8 hours. After he had bee working for 1 hour, his brother Johnny started helping him. It took them 3 more hours to finish. How long would it take Johnny to paint the house by himself?

Answer 1

Convert to hourly rates e g Carl 1/8 (of house) per hour etc

Answer 2

how do i do that?

Answer 3

can you give me the equation?

Answer 4

that means it took the two of them 3 hours to paint 7/8 of the house, if carl paints 1/8 per hour then he painted 3/8 in that hour, leaving 5/8 left for the brother to paint in that 3 hours, its asking how long it would take the brother to paint the whole house so we just set up a proportion