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The word percent means "per one hundred."
Percent values are suffixed by a
%
character.A percent is a fraction where the denominator is 100.
5% equals 5/100 15% equals 15/100 120% equals 120/100 37.5% equals 37.5/100Percent values can be written as a decimal number by multiplying the value by
0.01
.4% equals 4(.01) equals 0.04 11% equals 11(.01) equals 0.11 110% equals 110(.01) equals 1.10Decimal values can be written as percents by multiplying by 100%.
0.02 equals 0.02(100)% equals 2% 0.33 equals 0.33(100)% equals 33% 2.10 equals 2.10(100)% equals 210%Percents can be written as fractions by multiplying by
1/100
(or one onehundreth).5% equals 5(1/100) equals 5/100 25% equals 25(1/100) equals 25/100 110% equals 110(1/100) equals 110/100PurpleMath.com:: Converting Between Decimals, Fractions, and Percents [opens new window]
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The following algorithm converts a fraction into a percent.
a) divide the numerator by the denominator b) multiply the resulting decimal number by 100(%)Examples.
3/8 = 0.375; 0.375 * 100(%) = 37.5% 1/2 = 0.5; 0.5 * 100(%) = 50% 7/11 = 0.6364; 0.6364 * 100(%) = 63.64% 11/7 = 1.5714; 1.5714 * 100(%) = 157.14%The following algorithm converts a percent into a fraction.
a) write the percent as a fraction (n% = n/100) b) reduce the fraction, if possibleExamples.
25% = 25/100; 25/100 reduces to 1/4 62% = 62/100; 62/100 reduces to 31/50 202% = 202/100; 202/100 reduces to 2 1/50 1% = 1/100; 1/100 is reduced 0.2% = 0.2/100; 0.2/100 reduces to 0.1/50 or 1/500
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The percentage increase between two values is calculated as follows.
new value  original value  * 100 original valueThe percentage decrease between two values is calculated as follows.
original value  new value  * 100 original valueExamples
The Maricopa Community Colleges increased 200506 instate tuition rates by
$5
per credithour. The 200405 tuition rate was$55
.old rate: $55 [200405 rate] increase: $ 5 ["increase" implies addition] new rate: $60 [sum of $55 and $5] percentage increase: 60  55 5  =  = 0.0909 55 55 0.0909 * 100 = 9.09%The Maricopa Community Colleges increased 200607 instate tuition rates from
$60 per credithour
to$65 per credithour
.percentage increase: 65  60 5  =  = 0.0833 60 60 0.0833 * 100 = 8.33%
The Valley Metro Transit is considering decreasing bus fares by
$0.25
. Current bus rates are$1.25
per two hours of bus riding.current rate: $1.25 proposed decrease: $0.25 [the word "decrease" implies subtraction] new rate: $1.00 [difference of $1.25 and $1.00] percentage decrease: 1.25  1.00 0.25  =  = 0.2000 1.25 1.25 0.2000 * 100 = 20%PurpleMath.com:: "Percent of" Word Problems: General Increase and Decrease [opens new window]
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Percent problems come in many forms. Three popular forms are often worded as follows.
What is 'a' percent of 'b'? 'a' is what percent of 'b'? 'a' is 'b' percent of what?Here are some rules to map these type of percent word problems into equations.
"what" becomes a variable "is" becomes an equals operator "of" becomes a multiply operator1) What is
5%
of10
?n = 5% * 10 ...variable is named 'n' n = 5(.01) * 10 ...%5 converted to decimal n = 0.05 * 10 ...word "of" became times n = 0.5 ...decimal arithmetic 0.5 is 5% of 10 ...final answer2)
7
is what percent of49
?7 = n * 49 7 n * 49  =  49 49 1  = n 7 .143 = n .143 * 100 = 14.3 = n (final answer: 14.3%) 7 is 14.3% of 493)
4
is12%
of what?4 = 12% * n 4 = 12(.01) * n 4 .12 * n  =  .12 .12 33.3 = n 4 is 12% of 33.3External Hyperlinks
 PurpleMath.com:: Basic "Percent of" Word Problems [opens new window]
 WebMath.com:: Word Problems Involving Percents [opens new window]
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_______% of the five cells are red.
_______% of the five cells are green.
_______% of the ten cells are not white.
Shade 45% of the five cells.
Shade 0.5% of the five cells.
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MerriamWebster Online
[http://wm.com]
defines measurement as follows.1 : the act or process of measuring 2 : a figure, extent, or amount obtained by measuring : DIMENSIONMeasurements are used to measure stuff like time, temperature, length, weight, speed, money, power, and so on.
There are two primary measurement systems: US and Metric.
Each measurement system consists of many different units. For example, in the US, lengths are measured using units of inches, feet, yards, and miles. The metric system uses length units based on the meter (kilometer, millimeter, centimeter, and so on). [UNC.edu:: metric prefixes]
Let's use inch as a starting point. An inch is about the width of a man's thumb at the base of the nail and it is used to measure length.
Inches work well when measuring short lengths. Longer lengths are usually measured using other units of measurements such as feet and yards. Example: A football field is
3600 inches
in length, but we usually say it is100 yards
.Ratios have been established to convert from one unit of measure to another. The following are some US length ratios.
12 inches equals 1 foot 3 feet equals 1 yard 1760 yards equals 1 mileExercise: Convert
36 inches
tofeet
. We are given thatone foot
equalstwelve inches
.Setup two proportions and solve for the unknown. 1 ft. n ft.  =  12 in. 36 in. 1) multiply both sides by 36 in. 1 ft. n ft. 36 in. *  =  * 36 in. 12 in. 36 in. 2) solve for 'n' 1 ft. n ft. 36in.*  =  *36 in.12in.36 in.36 * 1 ft.  = n ft. 12 36 ft.  = n ft. 12 3 ft. = n ft. 36 inches equals 3 feet.Units of Measurement Resources
NIST.gov:: General Tables of Units of Measurement
National Institute of Standards and Technology
http://ts.nist.gov/WeightsAndMeasures/Publications/appxc.cfm
UNC.edu:: How Many?
University of North Carolina
http://www.unc.edu/~rowlett/units
Time
60 seconds per 1 minute 60 minutes per 1 hour 24 hours per 1 dayLet's compute how many seconds are in a day.
We want to solve the following. ? seconds  1 day We are given the following. 60 seconds 60 minutes 24 hours    1 minute 1 hour 1 day Multiply the three fractions together. The units of measurement "cancel" each other out. 60 seconds 60minutes24hours *  *  1minute1hour1 day 60 * 60 * 24 = 86,400 Answer. 86,400 seconds  1 dayA couple time and money quotes...
"Remember that time is money."
Benjamin Franklin"Minutes are worth more than money. Spend them wisely."
Thomas P. MurphyMoney
5 pennies per 1 nickel 2 nickels per 1 dime 5 nickels per 1 quarter 4 quarters per 1 dollarA penny is
one hundreth
of a dollar (i.e.$0.01
) and a dime isone tenth
of a dollar (i.e.$0.10
).A nickel is
%5
of a dollar (i.e.$0.05
) and a quarter is%25
of a dollar (i.e.$0.25
).Temperature (measure of molecular motion)
Degrees Fahrenheit are used to record surface temperature measurements by meteorologists in the United States. Most of the rest of the world uses degrees Celsius. Most of the scientific world uses Kelvin. [The word "degrees" is not used with Kelvin. In addition, Kelvin starts at "absolute zero;" therefore, there are no negative values. "Absolute zero" is the point at which all molecular motion stops.]
Formula: Fahrenheit to Celsius
°C = (°F  32) / 1.8 or Tc = (5/9) * (Tf  32) where Tc is temperature in degrees celsius Tf is temperature in degress fahrenheitFormula: Fahrenheit to Kelvin
K = (°F + 459.67) / 1.8The boiling point of sea water is
100 °C
.The freezing point of water at sea level is
0 °C
.The average room temperature is
20 °C
.The average human body temperature approximates
37 °C
.
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On 8 January 2007, NASA announced that the Moon will be metric leaving only the "United States, Liberia, and Burma still primarily using English units."
The metric system is also called the International System of Units (denoted by SI).
The following are base metric units of measurement.
length................ meter...... m mass.................. kilogram... kg time.................. second..... s electric current...... ampere..... A temperature........... Kelvin..... K amount of substance... mole....... mol luminous intensity.... candela.... cd volume................ liter...... L [nonSI]Metric Prefixes
10^{1} deka da 10^{2} hecto h 10^{3} kilo k 10^{6} mega M 10^{9} giga G 10^{12} tera T 10^{15} peta P 10^{18} exa E 10^{21} zeta Z 10^{24} yotta Y 10^{1} deci d 10^{2} centi c 10^{3} milli m 10^{6} micro u 10^{9} nano n 10^{12} pico p 10^{15} femto f 10^{18} atto a 10^{21} zepto z 10^{24} yocto y1 dekameter...... 10 meters 1 hectometer..... 100 meters 1 kilometer...... 1000 meters ... 1 gigameter...... 1,000,000,000 meters 1 decimeter...... 0.1 meter 1 centimeter..... 0.01 meter 1 millimeter..... 0.001 meter ... 1 nanometer...... 0.000000001 meterThe metric prefixes work on other base metric units.
1 kilogram....... 1000 grams 1 milligram...... 0.001 gram ... 1 nanogram....... 0.000000001 gram 1 hectoliter..... 100 liters 1 milliliter...... 0.001 liter ... 1 nanoliter...... 0.000000001 liter[nanovery, very, very small]
Update::2008.11.13
From nanotech...
"Sculpted using nanolithography by University of Michigan mechanical engineer, John Hart, each Obama face is composed of 150 million carbon nanotubes and measures half a millimeter across."NanoObama.com::Vote for Science
to hightech...
"Cisco predicts IP traffic will nearly double every two years, increasing at a combined annual growth rate of 46 percent from 2007 to 2012. That growth would result in an annual bandwidth demand on the world's IP networks of approximately 522 exabytes, or more than half a zettabyte. This demand on networks is equivalent to downloading 125 billion DVD movies per month." [...] "On the scalability front, the Cisco ASR 9000 offers up to six times the capacity of comparable edgerouter solutions, with up to 6.4 terabits per second of total capacity and up to four times the linecard speed available on the market, with 400 gigabits per slot."NewsFactor.com::Cisco Unveils 'ZettabyteEra' Router for Online Video
at Scottsdale Community College (SCC).
MathBabbler did not have a MAT082 class during the Spring 2008 semester, but during that semester, Dr. Art Decabooter stepped down as president of SCC. Notice how Decabooter's name starts with the metric prefix deca.BAB::Metric Prefixes: Is it Deca or Deka?
Drugs have taught an entire generation of Americans the metric system.  P. J. O'Rourke
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NIST.gov:: General Tables of Units of Measurement
National Institute of Standards and Technology
http://ts.nist.gov/ts/htdocs/230/235/appxc/appxc.htm
UNC.edu:: How Many?
University of North Carolina
http://www.unc.edu/~rowlett/units
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Tempe and Show Low are
163
miles apart. Calculate this distance inkilometers
.Given: 1 mi = 1.609344 km Solve: ??? kilometers  163 miles 1) setup a proportion ??? kilometers 1.61 kilometers  =  163 miles 1 mile 2) solve for ??? by multiplying both sides by 163 miles ??? kilometers 1.61 kilometers 163 miles x  =  x 163 miles 163 miles 1 mile ??? kilometers 1.61 kilometers163milesx  =  x 163miles163miles1mile1.61 x 163 equals 262.43 Answer: 163 miles is approximately equal to 262.43 kilometers[check answer] Google.com::Calculator:: 163mi to km
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Tempe and Superior are appoximately
52 miles
apart. Compute how many inches this is.Solve. ? inches  52 miles Given. 1 mile = 1760 yards 1 yard = 3 feet 1 foot = 12 inches 1) Convert 52 miles into yards. 1760 yards ? yards  =  1 mile 52 miles 52 miles equals 91,520 yards 2) Convert 91,520 yards into feet. 3 feet ? feet  =  1 yard 91,520 yards 91,520 yards equals 274,560 feet 3) Convert 274,560 feet into inches. 12 inches ? inches  =  1 foot 274,560 feet 3,294,720 inches equals 274,560 feet Answer. 52 miles equals 3,294,720 inches.
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Given.
60 seconds per 1 minute 60 minutes per 1 hour 24 hours per 1 dayLet's compute how many seconds are in a day.
We want to solve the following. ? seconds  1 day We are given the following. 60 seconds 60 minutes 24 hours    1 minute 1 hour 1 day Multiply the three fractions together. The units of measurement "cancel" each other out. 60 seconds 60minutes24hours x  x  1minute1hour1 day 60 * 60 * 24 = 86,400 Answer. 86,400 seconds  1 dayA couple time and money quotes...
"Remember that time is money."
Benjamin Franklin"Minutes are worth more than money. Spend them wisely."
Thomas P. Murphy
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The first definition for money given by MerriamWebster Online is as follows.
"1 : something generally accepted as a medium of exchange, a measure of value, or a means of payment: as a : officially coined or stamped metal currency"Here is only one of many good money quotes...
Money can't buy you happiness, but it does bring you a more pleasant form of misery.
 Spike Milligan (0191802002) { British actor and comic; more... } [money/happiness]In the United States of America we deal with monetary units of measurement such as pennies, nickels, dimes, quarters and dollars ($1, $5, $10, $20, $50, $100, ...; what about $2?).
Conversion ratios.
5 pennies per 1 nickel ( 5 cents; $0.05) 2 nickels per 1 dime ( 10 cents; $0.10) 5 nickels per 1 quarter ( 25 cents; $0.25) 4 quarters per 1 dollar (100 cents; $1.00)A penny is
one hundreth
of a dollar (i.e.1/100
or$0.01
) and a dime isone tenth
of a dollar (i.e.1/10
or$0.10
).A nickel is
%5
of a dollar (i.e.$0.05
) and a quarter is%25
of a dollar (i.e.$0.25
).Finance.Yahoo.com:: Currency Converter
Currency conversion examples.
 GDT::BAB:: Domain Names by the Euro
 GDT::BAB:: Scottsdalebased Canadian CompanyIsotechnika
 GDT::BAB:: U.K. Allocates Funds For Hector [04 April 2006]
That's my .02 cents on the subject.
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Temperature is a measure of molecular motion.
Here is a quote about temperature.
A Harvard Medical School study has determined that rectal thermometers are still the best way to tell a baby's temperature. Plus, it really teaches the baby who's boss.
 Tina Fey (1970???) { Saturday Night Live comedian; pic }Degrees Fahrenheit are used to record surface temperature measurements by meteorologists in the United States. Most of the rest of the world uses degrees Celsius. Most of the scientific world uses Kelvin. [The word "degrees" is not used with Kelvin. In addition, Kelvin starts at "absolute zero;" therefore, there are no negative values. "Absolute zero" is the point at which all molecular motion stops.]
Formula: Fahrenheit to Celsius
°C = (°F  32) / 1.8 or Tc = (5/9) * (Tf  32) where Tc is temperature in degrees celsius Tf is temperature in degress fahrenheitFormula: Fahrenheit to Kelvin
K = (°F + 459.67) / 1.8The boiling point of sea water is
100 °C
.The freezing point of water at sea level is
0 °C
.The average room temperature is
20 °C
.The average human body temperature approximates
37 °C
.The hottest recorded temperature in the United States is
56.7 °C (134 °F)
in Death Valley, California on 10 July 1913. The hottest temperature ever recorded on Earth is136 °F
at Al' Aziziyah, Libya in September of 1922.The coldest recorded temperature on earth was
128.6 °F
on 31 July 1983 at a Russian research station at Vostok, Antarctica.The following was copied from ClassZone.com
"The Vostok ice core provides the longest continuous record of Antarctic climatic history. Analysis of the core has been completed to a depth of 3350 meters, representing approximately 440,000 years of climate history."YouTube.com::How Hot Can It Get?
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