Grace Imson, MA
Math Instructor, City College of San Francisco
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Co-authored Articles (238)
How to
Use an Abacus
The abacus (the suanpan is the most useful variety) is a deceptively simple calculating tool still used all over the world. It's a useful learning device for the visually impaired, as well as for anyone who wants to lear...
How to
Calculate the Circumference of a Circle
Need to know how to find the circumference of a circle? Can't remember the circumference formula? Don't sweat it—we've got you covered. If you know the diameter, simply plug it into this formula: '''C=πd'''. Were you...
The Trachtenberg Method: Learn to Calculate Multi-Digit Numbers Quickly
Quick, easy techniques to add, multiply, and divide without breaking a sweat Do you wish you could do more math in your head? Do you find conventional arithmetic difficult? Then the Trachtenberg method is perfect for yo...
How to
Calculate Standard Deviation
Standard deviation tells you how spread out the numbers are in a sample. Once you know what numbers and equations to use, calculating standard deviation is simple!
How to
Do Long Division
A part of basic arithmetic, long division is a method of solving and finding the answer and remainder for division problems that involve numbers with at least two digits. Learning the basic steps of long division will al...
How to Calculate Pi
Calculate pi using the measurements of circle, an infinite series, Buffoon's Needle Problem, & morePi (π) is one of the most important and fascinating numbers in mathematics. Roughly 3.14, it is a constant that is used ...
How to
Calculate the Area of a Circle
Need to know how to find the area of a circle? This is a common geometry problem and figuring out the answer is pretty easy. In most cases, you can use the simple formula A=\pi r^2. If you don't know the radius, don't w...
How to
Do Division
Division is one of the 4 major operations in arithmetic, alongside addition, subtraction, and multiplication. In addition to whole numbers, you can divide decimals, fractions, or exponents. You can do long division or, i...
How to Memorize Pi: All the Best Methods
Learn the digits of pi with this helpful guidePi is the ratio of the circumference to the diameter (the diameter is 2 time tens of thousands of digits).
How to
Do Long Multiplication
Long multiplication can seem very intimidating, especially if you're multiplying two numbers that are pretty large. If you take it step by step, though, you'll be able to do long multiplication in no time. Get ready to a...
How to
Convert from Decimal to Binary
The decimal (base ten) numeral system has ten possible values (0,1,2,3,4,5,6,7,8, or 9) for each place-value. In contrast, the binary (base two) numeral system has two possible values represented as 0 or 1 for each pla...
How to Calibrate a Digital Scale With and Without Weights
Simple steps to get your scale to measure accurately Over time, your digital pocket scale can get uncalibrated, whether it’s from regular use, wear and tear, or moving it to a new location. If your scale is giving you ...
How to
Calculate Ratios
Ratios are mathematical expressions that compare two or more numbers. They can compare absolute quantities and amounts ''or'' can be used to compare portions of a larger whole. Ratios can be calculated and written in sev...
How to
Convert Radians to Degrees
Radians and degrees are both units used for measuring angles. As you may know, a circle is comprised of 2π radians, which is the equivalent of 360°; both of these values represent going "once around" a circle. Therefo...
How to
Calculate the Volume of a Cylinder
center A cylinder is a simple geometric shape with two equally-sized and parallel circular bases. Calculating the volume of a cylinder is simple once you know the formula.https://www.mathsisfun.com/definitions/cylinder.h...
How to Use the Percent Change Formula
Easily find percent increase or decrease with this simple equationLooking at the change in percent of a number, as opposed to the change in value, can give you a more useful representation of how something has increased...
How to
Measure an Angle Without a Protractor
The easiest way to measure an angle is to use a protractor. However, if you don't have a protractor handy, you can determine the size of an angle using the basic geometric principles of triangles. You'll need a scientifi...
How to
Read a Caliper
Calipers are measuring tools used to precisely determine the width of a gap or object, much more accurately than a tape measure or ruler. Besides digital models, which uses an electronic screen, a caliper can display the...
How to
Calculate Volume in Litres
A liter (or litre) is a metric unit used to measure volume or capacity. Liters are a common measurement often used to measure beverages and other liquids, such as a 2 liter bottle of soda. Sometimes you will need to calc...
Converting Minutes to Hours in Decimal or Hour & Minute Format
Quick and easy calculations for whichever hour format you needNot sure how to change a measure of time in minutes to one in hours? Not to worry! It's easy to make this conversion in just a few simple steps. We’ll show ...
