Math geniuses, unite! Can this be done?

Trent_Hatred

I'm given these numbers:

After - 3077.89
Tax 1 - 7%
Tax 2 - 7.5%

What I need to determine is what was the price before taxes added, as well as the individual tax amounts.

The final numbers are as follows:

Before - 2688.11
Tax 1 - 188.17
Tax 2 - 201.61

How would I go about reverse calculating this? Can it be done? The tax amounts are based on the "Before" number, not the after.

So, 7% of 2688.11 is 188.17.

Not sure if it's possible or not.

YappyDog

Add all your taxes together getting 14.5 percent

Divide your end result by 100% plus taxes of 14.5% gives you your starting amount.

3077.89 / 1.145 = 2688.11

From there you can calculate your individual taxes by multiplying again.

2688.11 * .07 = 188.1677

2688.11 * .075 = 201.60825

Trent_Hatred

Yar! Ok, that works ... but!

What if you've only got one of the taxes?

After - 33517.61

Tax 1 - 7%

Before - 31468.50
Tax 1 - 2049.11

33517.61 / 1.07 = 31324.86

YappyDog

7 percent of 31,468.50 is 2202.795

Those two added together = 33671.295

33671.295 / 1.07 = 31,468.50

Trent_Hatred

GAH!

Yappy, thank you a million. I was afraid I'd have to run some ridiculous loop through my DB in order to get those numbers.

Again, a sincere thanks. 🙂

Trent_Hatred

I think I'm confused.

Ok:

7 percent of 31,468.50 is 2202.795

Those two added together = 33671.295

33671.295 / 1.07 = 31,468.50

I'm not given the 31,468.50 number though, I'm given 33517.61.

So what I start out with is:

After - 33517.61
Tax 1 - 7%

and I'm trying to get:

Before - 31468.50
Tax 1 - 2049.11

YappyDog

Something's not right your numbers.

Your tax needs to be something close to .06511622 to get from your start to your finish numbers.

Trent_Hatred

...Frick, you're absolutely right.

7% of 31468.50 is 2202.795, not 2049.11

Going to have to figure that one out.