How does SPI = EV / PV rearrange to EV = SPI * PV?

  • Topic:
  • Thread starter Thread starter falcios
  • Start date Start date
  • Tags Tags
    Algebra Operations
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
2 replies · 2K views
falcios
Messages
3
Reaction score
0
How does this formula SPI = EV / PV rearrange to this formula EV = SPI * PV
Why does the operation change from multiply to divide?

Thanks for the help.
 
Mathematics news on Phys.org
We begin with:

$$SPI=\frac{EV}{PV}$$

If we next multiply both sides by $PV$, we get:

$$SPI\cdot PV=\frac{EV}{PV}\cdot PV=EV\cdot\frac{PV}{PV}=EV\cdot1=EV$$
 
-
The answer to your "why" question is this:

Division is the same as multiplying by a reciprocal, that is:

[math]\frac{a}{b} = a*\frac{1}{b}[/math]