Posts Tagged ‘numbers’
Friday, September 18th, 2009
How to Order Numeric Expressions
Description
A detailed tutorial on the ordering of numeric expressions. Step by step tutorial including several examples of how to order numeric expressions for reference.
Overview
Ordering numeric expressions is something most of you should be familiar with. When you order numbers, or numeric expressions, you either order them from the lowest number to the highest number or from the highest number to the lowest number. It’s not difficult if you know how to count. But what if you’re faced with an array of decimals, percents, mixed numbers, and fractions? How do you know which number goes where? You need to convert them all to the same – decimals are the easiest when you are converting numbers so you can order them. Then after you order them, simply replace the ones you converted back to the values that were given.
Tags: arithmetic, convert, decimals, expressions, fractions, highest, lowest, Math, mixed numbers, numbers, numeric, order, ordering numeric expressions, percents
Posted in Arithmetic | No Comments »
Friday, September 18th, 2009
Introduction to Irrational Numbers
Description
A detailed tutorial on the definition of an irrational number. Step by step tutorial including several examples of irrational numbers for reference.
Overview
An irrational number is a number that cannot be written as the ratio of 2 integers. However, this does not mean they have no place on a number line. One of the most famous irrational numbers is pi, which is approximately equal to 3.14 – however, this is just a simplified version of the actual number. Another famous irrational number is the square root of 2. This is equal to around 1.41. Both irrational numbers and rational numbers are real numbers, which include all integers.
Tags: arithmetic, imaginary, integers, irrational, Math, natural, number, numbers, pi, ratio, rational, real, sqrt(2), square root
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Thursday, September 17th, 2009
Introduction to Combinations
Description
A detailed tutorial on the solving of combinations. Step by step tutorial including several examples of how to solve combinations for reference.
Overview
Combinations are often used with permutations. A combination is actually just the written representation of the permutation – with the permutation, you figure out how many different combinations there are, but with combinations you actually write down what those combinations are, not just how many there is. Many people prefer permutations because permutations are a lot less work. However, combinations do come up frequently, most notably in logic courses like discrete math.
Tags: combination, combinations, discrete math, items, Math, multiplication, numbers, possibilities, precalculus, sets, statistics, variables
Posted in Algebra | No Comments »
Thursday, September 17th, 2009
Introduction to Permutations
Description
A detailed tutorial on the solving of permutations. Step by step tutorial including several examples of how to solve permutations for reference.
Overview
A permutation is an ordered sequence of elements, also known as a set. Basically, a permutation is when you have a set amount of possibilities to be one thing (typically a variable), and then you have one less than that number of possibilities for your next variable, etc. Often you can use this to figure out exactly how many possible combinations in a set there are. Permutations are used very often in math, all done slightly different depending on the branch of mathematics, but it is first introduced in precalculus.
Tags: items, Math, multiplication, numbers, permutation, permutations, possibilities, precalculus, sets, statistics, variables
Posted in Algebra | No Comments »
Thursday, September 10th, 2009
How to Round Numbers and Decimals
Description
This is a basic video tutorial on rounding numbers to the nearest 10, 100, and 1000. Many example problems are provided in this video.
Overview
Rounding is a very basic concept in math, but is used just as much in higher level math as in the basic classes. It is used a lot with statistics to make the information much easier to use. The basic rule of rounding is that any number 5 or over gets rounded up, and any number 4 or lower gets rounded down. This is very easy if you have to round to the nearest 10 – just round down or up accordingly. But what about rounding decimals? Decimals have the same basic principle for rounding, but can be difficult because you’re working backwards to eliminate something, not change something you already have. Let’s say you are given this decimal: 0.385630483. You want to round this down to three decimal places. So you take the very last number – 3. 3 falls in the category of 4 or lower, so the number after it does not get changed. So you can get rid of the 3. Now, look at the next number. The next number is an 8. 8 falls in the category of 5 or higher, so the number after it gets rounded up. The number after the 8 was a 4. When you get rid of the 8, you must change the 4 into a 5. So now, you look at the 5. The 5 is also in the category of 5 or above, so your next number, which was a 0, gets changed to 1. If you keep following this pattern all the way down the decimal line, your new decimal will be 0.386.
Tags: arithmetic, decimal place, decimals, Math, numbers, round, rounding
Posted in Arithmetic | No Comments »
