Answer:
They complete the hill in 8 hours
Step-by-step explanation:
We will need to solve these equations with a system of equations, so we need to isolate one variable in one of the equations and then replace it with another equation. After this, this means that Beatrice alone would construct the hill in 24 hours and Charlie 40. So, after finding the value A we will need to add A with B and C. This would get us [tex]0.125h^{-1}[/tex]. We will then divide [tex]\frac{1}{0.125h^{-1}}[/tex]. This will leave with 8h.
A= 7/120h
C=1/40h
B= 1/24h
