Basic Probability: Sample Space, Events and Examples with Dice, Coins and Cards
Probability puts a number on how likely something is. It runs from 0 (it cannot happen) to 1 (it always ... Read more
Neurochispas
Simple vs Compound Interest: Formulas, Examples and the Rule of 72
Interest is the price of using money. A bank pays it to you when you save, and you pay it ... Read more
Significant Figures and Rounding: Rules, Examples and Practice
A measurement is never exact. A ruler marked in millimeters cannot tell you that a rod is 7.4623 cm long, ... Read more
Temperature Scales: Celsius, Fahrenheit and Kelvin (History and Formulas)
Temperature tells you how hot or cold something is, but the number you read depends on the scale. Water freezes ... Read more
US Customary vs Metric Units: Exact Definitions and Conversions
Americans measure height in feet and inches, road trips in miles, and gasoline in gallons, while nearly everyone else uses ... Read more
Metric System: SI Units and Prefixes (Nano to Giga)
The metric system measures everything with one set of base units and one set of prefixes that multiply by powers ... Read more
Rule of Three: Direct, Inverse and Compound Explained
The rule of three finds a fourth number when you know three and the quantities are linked by proportion. If ... Read more
How to Calculate a Weighted Average: Grades, Credits and the Final Exam
A simple average treats every value as equally important. That is wrong when some values count more than others: a ... Read more
Mean, Median and Mode: When Each One Is the Better Summary
The mean, the median and the mode all try to answer the same question: what is a typical value in ... Read more
How to Calculate Percentages: Discounts, Increases and Percent Change
A percent is a fraction with a denominator of 100. Saying 35% means 35 out of every 100, or $latex ... Read more