Question #1f3d8

1 Answer
Jun 17, 2017

The base cost is #$7.05#

Explanation:

So anytime you buy something at the store it obviously has two different charges. There is the cost of picnic cooler and the tax added to it.

#"Total bill"="Base cost" + 6%" of Base cost"#

The percentage is, mathematical, an amount out of #100%#. So, the math of the #6%# is simply that number divided by #100%#.

#6%=(6%)/(100%)=0.06#

Notice the final percentage (as a decimal) doesn't have a #%# symbol. You can think of them as having been "cancelled" in the previous fraction. So we have

#"Total bill"="Base cost" + 0.06xx("Base cost")#

Now, fill in the math sentence with the given numbers. And we can rewrite the word "#"Base cost"#" with the shortcut variable, #x#

#7.95=x+0.06x#

#7.95=1.06x#

#7.95/1.06=(cancel(1.06)x)/cancel(1.06)#

#7.05=x#

So the base cost is #$7.05#