Thursday, December 19, 2013

Sophia's Percent Post

A percent is a equivalent number out of 100.

100 percent means everything, 100/100
To find 100 percent you have to divide the equivalent number by 1.

50 percent means 50/100, 1/2, divided by 2, half.
To find 50 percent you have to divide the equivalent number by 2.

25 percent means 25/100, 1/4, quarter, divided by 4.
To find 25 percent you have to divide the equivalent number by 4.

10 percent means 10/100, 1/10, divided by 10.
To find 10 percent you have to divide the equivalent number by 10.

1 percent means 1/100, divided by 100.
To find 1 percent you have to divide the equivalent number by 100.

3)

3) Converting Percents Fractions and Decimal

To convert a fraction to a decimal you have to divide the numerator and the denominator to get a decimal number.
ex. 3/40 = 0.075
3 divided by 40 makes 0.075

Now to convert a decimal to a percent you have to multiply my 100, because percents are out of 100 and also a decimal is out of 1.
ex. 0.075*100 = 7.5 so thats 7.5%
0.075 multiplied by 100 makes 7.5

To convert a percent to a fraction you have to get the decimal which if it was 7.5% you divide that by 100  which makes 0.075. Since the place holder is in the thousandths place we put the denominator 1000 and then 75 on the numerator. Then we divide by 2 to get a equivalent fraction.
ex.
75/1000 divide until we get an equivalent fraction = 3/40

4)
20% of 60
Calculator:

20/100= 0.2        0.2*60=12    therefore 12 is 20 percent of 60

Mental Math:

20% of 60 0.1% of 40

250% of 400

5) Combining Percents

Which is a better deal?
50% off or 25% off of an already reduced price of 25%
If the price was \$60.00

to get 50 percent you divide 50 by 100 to get the decimal of 50. Then the number will be 0.5, so 0.5 * 60 = 30.00 so 50% of 60.00 is \$30.00.

Now 25% of an already reduced price of 25%.
First get 25% of 60
Which will be 25/100 because all percents a out of 100. Then that would be 0.25, 0.25 * 60 = 15 then
60- 15 = 45.00
Then there will be a new total  which is \$45.00 Then repeat what you did before but instead of the 60 which was the old total it will be 45.00 so 45 -15  = 40.00

So now you know 50% is better then 25% off of an already reduced price of 25%.

Discount is what you save
Sale price is what you pay
Total price is what you pay with the taxes