Work problems

Pedro can paint a fence 50% faster than Juan and 20% faster than Pilar and together they can paint a given fence in 4 hours. How long will it take Pedro to paint the same fence if he had to work alone? Solution: Let Rate of pedro = 1/tpedro = x Rate of juan = .50x Rate of pilar = .80x (x+.50x+.80x)4=1 2.3x=1/4 x=5/46 5/46 = 1/tpedro tpedro=46/5 =9.2hours Is this solution correct because the book says the answer is 10hours.

Consider these:

  • 1.50*Rate of Juan = Rate of Pedro
    Rate of Juan = (2/3)*Rate of Pedro
  • 1.20*Rate of Pilar = Rate of Pedro
    Rate of Pilar = (5/6)*Rate of Pedro