1.the sales tax rate in a certain state is 8%. how much would you pay in total for a taxable item that costs $25.25?
2.alicia answered 20 out of 25 problems correctly on a test. what percent did she get correct?
3.jim bought a fishing rod for $42. this price was 70% of the original price. what was the original price?
4.an auctioneer sold items totaling $42,000. if her rate of commission was 7%, what was her income from commissions?
5.at a local hardware store, ms. jones learned that 1 would cost her $.50, 12 would cost $1.00, and the price of 144 would be $1.50. what was ms. jones buying?
6.people sometimes use credit cards to purchase items they can’t afford to pay for at the moment of purchase. if you’re one of these people, you should know that the monthly finance charge on credit purchases is based on percent. let’s say you have an outstanding balance of $800 on your credit card. the credit card company charges 1.6% per month. what finance charge will you have to pay for one month?

For numbers 1, 2, 3, 4, and 6 you just need to remember this formula:

P = r x b
where: P = Percentage (Portion)
            r = rate
            b = base amount

1. Your given for number 1 is as follows:

rate = 8%
Base amount = $25.25

You are looking for how much you would pay in total. First you need to find out how much your going to pay in taxes, based on the base amount. To get that, you need to convert the rate in its decimal form by dividing it by 100. 

rate = 8/100 = 0.08

Next you need to find how much you will pay in taxes, you can do that by using the formula: 

P = r x b
   = 0.08 x $25.25
   = $2.02  This is how much you will pay in taxes. 

To get the total amount you will pay, just add it to the original price:

$25.25 + $2.02 = $27.27

2. Your given will be:
p = 20
b = 25
r = ?

All you have to do is input what you know in the formula:

P = r x b
20 = r x 25

Transpose the 25 to the other side of the equation to get the rate and divide:

20/25 = r
0.8   = r
 
For this case it is asking for the rate in percent, all you need to do is multiply your computed rate by 100% and you will get 80%.

3. If your given would be:

P = $42.00
r = 70%
b = ?

Base is the unknown here, because you are looking for the original price. So we put this into our equation again:

$42.00 = 0.70 x b

Transpose the 0.70 to the other side of the equation again and divide:

$42.00/0.70 = $60.00

The original price was $60.00

4. The given would be:

P = ?
r = 7% or 0.07
b = $42,000

We are looking for how much he got, or the portion he got, so we are looking for the percentage. Input what you know into our formula:

P = 0.04 x $42,000
  =  $2,940.00

6. Your given would be as follows:
P = ?
r = 1.6% or 0.016
b = $800

You are looking for how much you would pay in finance charge, or the portion that will be added, based on your base amount so you will be looking for the percentage. Input your given into the formula:

P = 0.016 x $800
   = $12.80 

As for number 5, that is a trick question. The prices are different and no matter what formula you will use, you will not come up with a mathematical sound answer. Consider the situation, what can you buy in  local hardware store that has  1, 12, and 144? The answer is HOUSE NUMBERS.

Where are the calculations?