Greetings!
"
Solve for f:
![1/f=1/x+1/y](https://tex.z-dn.net/?f=1%2Ff%3D1%2Fx%2B1%2Fy)
".
Multiply both sides by
f.
![(1/f)*f=(1/x+1/y)*f](https://tex.z-dn.net/?f=%281%2Ff%29%2Af%3D%281%2Fx%2B1%2Fy%29%2Af)
Simplify.
![1=(fx+fy)/xy](https://tex.z-dn.net/?f=1%3D%28fx%2Bfy%29%2Fxy)
Multiply both sides by
xy.
![(1)*xy=((xf+yf)/xy)*xy](https://tex.z-dn.net/?f=%281%29%2Axy%3D%28%28xf%2Byf%29%2Fxy%29%2Axy)
Simplify.
![xy=xf+yf](https://tex.z-dn.net/?f=xy%3Dxf%2Byf)
Factor out
f.
![xy=f(x+y)](https://tex.z-dn.net/?f=xy%3Df%28x%2By%29)
Divide both sides by
x+y.
![(xy)/x+y=(f(x+y))/x+y](https://tex.z-dn.net/?f=%28xy%29%2Fx%2By%3D%28f%28x%2By%29%29%2Fx%2By)
Simplify.
![(xy)/(x+y)=f](https://tex.z-dn.net/?f=%28xy%29%2F%28x%2By%29%3Df)
![f=(xy)/(x+y)](https://tex.z-dn.net/?f=f%3D%28xy%29%2F%28x%2By%29)
Had to change the variable as Brainly thought it was a swearword. Sorry.
Hope this helps.
-Benjamin
You can use a proportion to get the answer $162.50
$39/6hours = X/25hours (cross multiply)
x=$162.50
Answer:
c 58
Step-by-step explanation:
Answer:
C) ![1\frac{6}{100}](https://tex.z-dn.net/?f=1%5Cfrac%7B6%7D%7B100%7D)
Step-by-step explanation:
Hope this helps!