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Frequently Asked Questions about Math

What is math?

Math is a shortened form of the word mathematics. Mathematics is the study of numbers, quantities, structure, and space.


What is mean?

Mean is another word for average. Finding the mean is finding the central point in a set of numbers. To do this, add up all your values and then divide by the number of values you are given.

Ex. Find the mean of the set: {100, 98, 89, 92, 81}.

\(\large \frac{100+98+89+92+81}{5}=\frac{460}{5}=92\)

The mean of this set is 92.

Watch a Video on Mean, Median, and Mode

What is mode?

Mode is the most frequently occurring value in a set of data. It is possible to have more than one mode in a set.

Ex. What is the mode of the set: {11, 13, 21, 11, 19, 13, 11, 2}?

The mode is 11 because it is included three times in the set, while every other number is included only once or twice.

What is range?

Range is the distance between the largest and smallest values in a set of numbers.

Ex. Find the range of the set: {3, 11, 19, 1, 7}.

Largest Number: 19

Smallest Number: 1

19 – 1 = 18

The range of this set of numbers is 18.

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What is pi?

Pi (π) is a Greek letter that represents the ratio of a circle’s circumference to its diameter. It is a never-ending number that cannot be written as a fraction, which means it is irrational. The approximate value of pi is 3.14.

What is a function?

A function is a relation between inputs and outputs in which every input has exactly one output.

You can tell if an equation is a function by graphing it and performing the vertical line test. To do this, imagine a vertical line is traveling across the x-axis. If at any x-value the line hits two different points, or y-values, your equation has failed the vertical line test and is not a function.

Ex. y = x is a function because for every x-value there is exactly one y-value.

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What does product mean?

The product of numbers is the answer you get when you multiply those numbers together. In other words, a product is an answer to a multiplication problem.

Ex. What is the product of 3 and 4?

3 x 4 = 12

The product of 3 and 4 is 12.

What is a variable?

A variable is a symbol, typically an English or Greek letter, that represents an unknown value.

Ex. In the expression: \(x^{2}+2y-3z\), x, y, and z are all variables.

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What is a constant?

A constant is an unchanging number, or a value that does not change.

Ex. In the expression: \(3x^{2}+4y+5z\), 3, 4, and 5 are all constants.

What is circumference?

Circumference is the perimeter of a circle. It can be found by multiplying the circle’s diameter by pi, or by doubling its radius and then multiplying by pi.

C = πd                     or                     C = 2πr

Ex. What is the circumference of a circle with a radius of 5 cm?

C = 2πr

C = 2π(5 cm)

C = 10π cm ≈ 31.4 cm

Watch a Video on Circumference