Grace Imson, MA
Math Instructor, City College of San Francisco
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Co-authored Articles (237)
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...
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
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 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
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...
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
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 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
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 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
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 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 Slope of a Line
Learn to calculate the slope of a line with these simple methods If you’re taking algebra, finding the slope of a line is an important concept to understand. But there are multiple ways to find the slope, and your teac...
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...
How to
Calculate Percentage Increase
Knowing how to calculate percentage increase is useful in a variety of situations. For instance, even when watching the news, you'll often hear a change described in large numbers without any percentage to give them cont...
How to
Convert Milliliters (mL) to Grams (g)
center Converting from milliliters (mL) to grams (g) is more complicated than plugging in a number, because it converts a volume unit, milliliters, to a mass unit, grams. This means each substance will have a different f...
How Big Is an Inch? Here's How to Measure Accurately
Learn to measure in inches using rulers, everyday items, or by converting from metric units Measuring objects in inches might seem straightforward. But what if you’re not accustomed to using a ruler or don’t have one...
How to
Convert from 24 Hour to 12 Hour Time
If you’ve ever been stumped when you see a clock read something like 14:24, it's probably because you’re unfamiliar with 24-hour time. This form of timekeeping is commonly used in the U.S. military, Europe, and other...
How to Find Horizontal Asymptotes: Rules for Rational Functions
If you see a dashed or dotted horizontal line on a graph, it refers to a horizontal asymptote (HA). In a rational function, an equation with a ratio of 2 polynomials, an asymptote is a line that curves closely toward the...
How to
Find the Y Intercept
On their own, y-intercepts aren’t complicated at all—they’re simply points where the graph of the equation intersects with the Y-axis. But how are you supposed to find a y-intercept when you only have a limited amo...
