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- Thread starter falcios
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\(\displaystyle CPI=\frac{EV}{AC}\)

Now, multiply both sides by \(\displaystyle \frac{AC}{CPI}\):

\(\displaystyle CPI\cdot\frac{AC}{CPI}=\frac{EV}{AC}\cdot\frac{AC}{CPI}\)

\(\displaystyle AC\cdot\frac{CPI}{CPI}=\frac{EV}{CPI}\cdot\frac{AC}{AC}\)

\(\displaystyle AC\cdot1=\frac{EV}{CPI}\cdot1\)

\(\displaystyle AC=\frac{EV}{CPI}\)

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You want to multiply both sides by $PV$ to isolate $EV$.also $SPI=EV/PV$ to $EV=SPI*PV$

it should be $SPI=EV/PV$ to $EV=SPI/PV$ you divide both sides by $PV$ to isolate $EV$

- Feb 29, 2012

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Falcios, you are right. They are mathematically equivalent, as both Mark and Karush have shown you. However, what I think is really the issue here is:

The answer is that each version helps you calculate one quantity in terms of the others. When you write

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

you can find the value of SPI in terms of EV and PV. If, for some reason, you are given SPI and PV, you can find the value of EV in terms of these. Likewise, you can find the value of PV in terms of SPI and EV by doing the calculation

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

In other words,

Hope this has helped.

Cheers!