Respuesta :
In order to find the number of hours of work at which they will have the same amount, you will need to find both their equations and then equalize them to find when they are the same.
Let x be the number of hours
Fernando: intial 10$ = constant and we multiply x by the 4$ he takes per hour. The whole has to be multiplied by 0.30 (30%) since that is the only part he keeps
Therefore, yf=0.3(4x+10)
Brenna: same logic
yb=0.25(6x)
To find when they are equal:
yf=yb
0.3(4x+10) = 0.25(6x)