simple math question !!! HELPP !!!

Okay.

This, I can do.

I assume GST means tax of some sort.

The price with tax is $1506.35, ( I hope that's a widescreen, lol).

The tax is 7% on top of the retail price, which is 100%.

So, $1506.35 is 107% of the price.


To work things out simply:

To find the 100% of the price-the price before tax, we multiply $1506.35 times (100/107).

Using my $4 calculator from Wal-Mart, that gives me $1407.80.

Okay?

The trick is to realize that $1506.35 is not the full price-it is 107% of the full price. Or, stated another way, the Price with tax is 1.07 of the actual price. After that, things fall into place.

To simply the math even further, solve for (100 / 107) first, (which is 0.9346) then multiply by the price with tax, ($1506.35).

Finally, you can get the same answer by the following formula.

Actual price = Price with tax/tax rate plus 100%

So here, the actual price = $1506.35 / (7% + 100%).

Actual price = $1506.35 / 107%

Or, since 107% is another way of saying 1.07

Actual price = $1506.35 / 1.07 = $1407.80.

If the sales tax were 8%, it would be

Actual price = Price with tax / 1.08

Hope this helps.

A more algebraic approach (doing the same thing) would be:
x=base price
.07x=tax
1.07x=total cost
1.07x=1506.35
x=1506.35/1.07=1407.80