Everyday Math
Percentages: a history and practical guide
A CalculatorWiser guide to parts per hundred in trade, finance, and data.
1,677 words · 8 min readRead article →Everyday Math Articles
Explore articles, explainers, and calculator-linked guides in Everyday Math.
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24 matching posts
Everyday Math
Ratios and proportions
A CalculatorWiser guide to comparing quantities and scaling relationships.
1,846 words · 9 min readRead article →Everyday Math
What is a unit rate?
A quick Math Minute explaining what is a unit rate.
85 words · 1 min readRead article →Everyday Math
What is percent change?
A quick Math Minute explaining what is percent change.
111 words · 1 min readRead article →Everyday Math
How the Split Bill Calculator Works
Split a bill with tip among multiple people.
368 words · 2 min readRead article →Everyday Math
How the Lottery Odds Calculator Works
Calculate the number of possible lottery combinations n choose k.
423 words · 2 min readRead article →Everyday Math
How the Random Number Generator Works
Generate a random integer between a minimum and maximum.
365 words · 2 min readRead article →Everyday Math
How the Password Strength Calculator Works
Estimate password strength from length and character variety.
418 words · 2 min readRead article →Everyday Math
How the Reading Time Calculator Works
Estimate reading time from word count and reading speed.
369 words · 2 min readRead article →Everyday Math
How the Words Per Page Calculator Works
Calculate average words per page.
421 words · 2 min readRead article →Everyday Math
How the Electricity Cost Calculator Works
Estimate electricity usage and cost from appliance wattage and time.
374 words · 2 min readRead article →Everyday Math
How the Driving Carbon Calculator Works
Estimate CO₂ emissions from driving distance and fuel economy.
423 words · 2 min readRead article →Everyday Math
How the Dog Age Calculator Works
Convert a dog's age to a simple human-age equivalent.
366 words · 2 min readRead article →Everyday Math
How the Cat Age Calculator Works
Convert a cat's age to a simple human-age equivalent.
421 words · 2 min readRead article →Everyday Math
How the Pool Volume Calculator Works
Estimate rectangular pool volume in gallons.
369 words · 2 min readRead article →Everyday Math
How the Aquarium Volume Calculator Works
Calculate aquarium volume in US gallons from inch dimensions.
369 words · 2 min readRead article →Everyday Math
How the Tip Percentage Calculator Works
Calculate tip as a percentage of the pre-tip bill.
368 words · 2 min readRead article →Everyday Math
How the Discount Savings Calculator Works
Calculate dollar savings from original and sale price.
421 words · 2 min readRead article →Everyday Math
How the Cost Per Person Calculator Works
Calculate shared cost per person.
366 words · 2 min readRead article →Everyday Math
How the Electricity Cost Per kWh Calculator Works
Calculate electricity cost per kilowatt-hour.
372 words · 2 min readRead article →Everyday Math
How the Water Cost Per Gallon Calculator Works
Calculate water cost per gallon.
371 words · 2 min readRead article →Everyday Math
How the Gas Cost Per Therm Calculator Works
Calculate natural-gas cost per therm.
426 words · 2 min readRead article →Everyday Math
How the Pages Per Day Calculator Works
Calculate pages read per day.
366 words · 2 min readRead article →Everyday Math
How the Reading Days Calculator Works
Estimate days required from pages remaining and pages read per day.
370 words · 2 min readRead article →