Tuesday, December 17, 2013

Jonathan's Percent Post

A percent is an equivalent fraction out of one hundred.

100 percents mean a whole or everything.
To find 100 percent you divide the number by one.

50 percent means half or 50/100.
To find 50 percent you divide the number by two.

10 percent means 10/100 or 1/10.
To find 10 percent you divide the number by ten.

25 percent means 25/100 or 1/4.
To find 25 percent you divide the number by four.

1 percent means 1/100.
To find 1 percent you divide the number by one hundred.

Representing Percents

a) 180% means 180 out of 100 or 180/100 or 1.80/1.8

180%

b) 0.6% means 0.6 out of 100 or 0.6/100 or 0.006

0.6%

c) 12 3/8% means 12 3/8 out of 100 or 12 3/8 /100 or 0.12375

12 3/8%

Converting a fraction to a decimal and a percent
3/40 also means 4 divided by 40. 3/40=0.075/1(decimal).
0.075/1 x 100=7.5% out of 100. But that is a ratio, not a fraction.

Converting a decimal to a percent and a fraction
0.0064 x 100=0.64%
0.64/100 x 100=64/10000 divided by 8=8/1250 divided by 2=4/625

Convert a percent to a decimal and a fraction
0.3/100=0.003
0.3/100 x 10=3/1000

convert from Decimals to Percents to Fractions:
26%/100=0.26x100=26% out of 100. 26/100 divided by 2=13/50 which is the fraction.
7/10=0.7x100=70%. 70/100 divided by 10=7/10.
0.024x100=2.4%. 2.4/100 divided by 2=1.2/50 divided by 2=0.6/25

20% of 60                              percent/ number                                   20% of 60 is 12.
100   /     60
divided by 5       20    /     12         divided by 5
20/100= /60
20x60=1200
1200/100=12

0.1% of 40                             percent/number
100    /     40
divided by 1000         0.1   /    0.04                divided by 1000
0.1/100= /40
40x0.1=4
4/100=0.04

250% of 400                       percents/number
100   /     400
multiply by 2.5         250   /    1000       multiply by 2.5
250/100= /400
400x250=100000
100000/100=1000

50% of or 25% off of an already reduced price of 25%:
50% off:                                                           25% off:              25% off of an already reduced price 25%:
50/100= /200                                                   25/100= /200      25/100= /150
200x50=10000                                                200x25=5000     150x25=3750
10000/100=100                                               5000/100=50      3750/100=37.50

50% of is better than 25% off of an already reduced price of 25% because 50% of goes straight to the half of the price. But 25% off of an already reduced price of 25% is more expensive because it cuts the half price in half which makes the price a different 100%.