Using a new lawn mower, Abby can mow the lawn in 2 hours. Her sister Carla used an older lawn mower and takes 3 hours to mow the same lawn. How long will it take them if they work together?

Respuesta :

So rates are the lower number of a fraction. 

So it would be:[tex] \frac{x}{3} + \frac{x}{2} = 1 [/tex]  Then cross muitply. 

2x + 3x = 6

5x=6 

x= [tex] \frac{6}{5} hours[/tex]