Sofia can type the work in 10 hours. Nova can do it in 15 hours. They work together for 4 hours, then Sofia and Nova finish the job. How long did it take to do the entire job?

Answer:2 days.Step-by-step explanation:Let, Sofia can type the x amount of work in 10 hours. So, in one hour Sofia can type [tex]\frac{x}{10}[/tex] amount of work. Again, Nova can type x amount of work in 15 hours. So, in one hour Nova can type [tex]\frac{x}{15}[/tex] amount of work. Hence, if they work together, they can type [tex]\frac{x}{10} + \frac{x}{15} = \frac{6x + 4x}{60} = \frac{10x}{60} = \frac{x}{6} [/tex] amount of work in one hour. Therefore, working together they can type the x amount of work in [tex]\frac{x}{\frac{x}{6} } = 6[/tex] days. So, they have to work for (6 - 4) = 2 days more to finish the work. (Answer)