isolating denominator with fractions on both sides and all variables

Question

S/B = M/F Solve for B, I've spent the last few hours watching videos and trying to find someone who can explain how to do this but for some reason I can't find any good explanations. I've just started to get back into math after many years and there's definitely some skill loss.

Answer 1

S/B=M/F solve for B

Need to know!

1. Reciprocals
2. When you do something to one side of an equation you must do the same to the other side.

The goal of the equation is solving for B so you need to put B on one side by itself. To do that, the reciprocal of M/F is F/M So......

multiply M/F by F/M and you get 1 and what you do to one side of the equal sign you do to the other side

So the equation looks like this

F/M times S/B= M/F times F/M (when you do the math) it looks like this ....

FS/MB=1

and here B is in the denominator so it really looks like this FS/M times 1/B = 1and the reciprocal of 1/B is B

Now multiply FS/MB by B because you want to isolate B and you get

B times FS/MB=1 times B

the B’s to the left of the = sign cancel out so the equation looks like

FS/M=B