Real applications of formulas

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What’s a formula good for?

Transcript of Real applications of formulas

Page 1: Real applications of formulas

What’s a formula good for?

Page 2: Real applications of formulas

Physicist Writes a Better Formula to Predict Baseball Success

W1/L1 = (RPG1/RPG2)^a (SLG1/SLG2)^bwhere a = 0.723 (RPG1 + RPG2)^.373 and b = 0.977 (RPG1 + RPG2)^( -.947)

Finds how the distribution of a team's runs can affect the team's winning percentage.

http://www.sciencedaily.com/releases/2010/03/100301141852.htm

Page 3: Real applications of formulas

Predicting your Optimal Proposal Age

http://www.dailymail.co.uk/news/article-1250250/Revealed-The-mathematical-formula-predicts-best-age-engaged.html

Page 4: Real applications of formulas

Predicting how tall your child will be

FOR BOYS1. Take each parent's height and add them together. If using the english system, total the number of inches. If using metric, add the centimeters together.2. Divide that number by 23. Add 2.5 inches to that number if using the english system. Add 6.5 centimeters to the number if using metric.4. This number is the midparental height for boys5. This number plus or minus 4 inches (or plus/minus 10 centimeters) is the range in which you could expect your son to fall.

FOR GIRLS1. Take each parent's height and add them together. If using the english system, total the number of inches. If using metric, add the centimeters together.2. Divide that number by 23. Subtract 2.5 inches to that number if using the english system Subtract 6.5 centimeters to the number if using metric4. This number is the midparental height for girls5. This number plus or minus 4 inches (or plus/minus 10 centimeters) is the range in which you could expect your daughter to fall.

http://www.ivillage.com/predicting-how-tall-your-child-will-be/6-n-136625

Page 5: Real applications of formulas

Predicting Your Day Of BirthJanuary, October = 0 Sunday = 0May = 1 Monday = 1August = 2 Tuesday = 2February, March, November = 3 Wednesday = 3June = 4 Thursday = 4September, December = 5 Friday = 5April, July = 6 Saturday = 6

1 - Drop the "19" in the year of birth 2- Divide this number by 4 and drop the remainder3- Add this answer to year of birth 4- Add the day of the month of birth to this total 5- From the first formula, add the value of the month 6- Divide this total by 7 7- Take this remainder (0) and apply this number to the number of days

http://www.pedagonet.com/quickies/qki105.htm

Page 6: Real applications of formulas

Formula to find out baby’s sex

 Option #1: Age of the mother when she got pregnant + her month of birth + month of conception (normally 14 days after the first day of the menstrual period) = if result is odd it is a boy if it is even it is a girl.

Option #2: Age of the mother + the month in which she got pregnant. If result is even it is a boy, if it is odd, girl.

http://www.home-remedies-site.com/boy-or-girl.htm

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Formula for Estimating Energy Consumption

Wattage × Hours Used Per Day ÷ 1000 = Daily Kilowatt-hour (kWh) consumption

Examples:Window fan:(200 Watts × 4 hours/day × 120 days/year)  ÷  1000= 96 kWh × 8.5 cents/kWh= $8.16/year

Personal Computer and Monitor:(120 + 150 Watts × 4 hours/day × 365 days/year)  ÷  1000= 394 kWh × 8.5 cents/kWh= $33.51/year

http://www.energysavers.gov/your_home/appliances/index.cfm/mytopic=10040

Page 8: Real applications of formulas

How to Calculate Loan Amortization Schedules

•The following assumes a typical conventional loan where the interest is compounded monthly. •P = principal, the initial amount of the loan•I = the annual interest rate (from 1 to 100 percent)•L = length, the length (in years) of the loan, or at least the length over which the loan is amortized.•J = monthly interest in decimal form = I / (12 x 100)•N = number of months over which loan is amortized = L x 12

http://www.hughchou.org/calc/formula.html

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How to find your Body Mass Index

BMI = Weight in Pounds x 703 Height in inches x Height in inches

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How to find your Basal Metabolic Rate

Women: BMR = 655 + ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years )

Men: BMR = 66 + ( 6.23 x weight in pounds ) + ( 12.7 x height in inches ) - ( 6.8 x age in year )

http://www.bmi-calculator.net/bmr-calculator/bmr-formula.php

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How to find your daily caloric needs

http://www.bmi-calculator.net/bmr-calculator/harris-benedict-equation/

Page 12: Real applications of formulas

Formula to find the distance between two points on the Earth

http://en.wikipedia.org/wiki/Haversine_formula

For any two points on a sphere:

wherehaversin(θ) = sin2(θ/2) = (1−cos(θ))/2d is the distance between the two pointsR is the radius of the sphere,φ1 is the latitude of point 1,φ2 is the latitude of point 2, andΔλ is the longitude separation,

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The Flesch Reading Ease Readability Formula

http://www.readabilityformulas.com/flesch-reading-ease-readability-formula.php

RE = 206.835 – (1.015 x ASL) – (84.6 x ASW) 

RE = Readability Ease ASL = Average Sentence Length (i.e., the number of words divided by the number of sentences) ASW = Average number of syllables per word (i.e., the number of syllables divided by the number of words) 

The output, i.e., RE is a number ranging from 0 to 100. The higher the number, the easier the text is to read. 

• Scores between 90.0 and 100.0 are considered easily understandable by an average 5th grader.• Scores between 60.0 and 70.0 are considered easily understood by 8th and 9th graders.• Scores between 0.0 and 30.0 are considered easily understood by college graduates. 

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How much should you spend on a house?

According to Garth Turner, The percentage P of one’s net worth a home should represent is equal to P = 90 – x, where x is one’s age

http://virtualmathtutor.blogspot.com/2011/07/garth-turners-formula-of-percentage-of.html

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When will insurgent attacks occur next?

http://www.npr.org/2011/07/31/138639711/math-can-predict-insurgent-attacks-physicist-says