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Various worksheets on TONS of math topics you can generate for free!
Basic operations worksheet generator is updated! Make worksheets for whole numbers or integers - all four operations, including add & subtract or multiply & divide - horizontal or vertical - add a border and/or extra workspace, use a variable, and more.
Advice, reviews, and resources to help you choose a math curriculum!
Online math games, tutorials, and activities
Games you can play online, interactive tutorials, fun math websites and more. Arranged by topic/level for ease of use.
Learn how to TEACH concepts or about general concerns in math education.
In-depth reviews of math products
Math help & tutoring
A list of free message boards, math help websites, and online tutoring services.
Fun and games
I have two games on my site, plus links to many.
Game: Choose Math Operation
Word guess game (easy hangman)
Word guess game (difficult)
Dividing decimals by decimals - a video and an online lesson
Why do we move the decimal point in both the dividend and the divisor when dividing decimals by decimals? It is because both the dividend and the divisor are multiplied by 10, 100, 1000, or some other power of ten. In the video below, I aim to make sense of this "rule". Please see also the lesson that continues below the video. The lesson are taken from Math Mammoth Decimals 2 book ($4.00 download). The book has more problems than shown in this online lesson.
Divide Decimals by Decimals
The above problems illustrate a way to solve decimal division problems. You noticed that in each case, the quotients (answers) were the same! And it is no wonder. Think of it as, “How many times does the divisor fit into the dividend?” 0.02 fits into the 0.06 as many times as 2 fits into 6. Or, 0.007 fits into 0.35 as many times as 7 fits into 350.
If we have a more difficult decimal division problem, such as 3.439 ÷ 5.6, we can transform it into a problem with the same answer, but with a whole-number divisor, which can be solved with long division.
Look at the problems in #1 again, this time moving from the bottom up. In each step, the dividend increases by a factor of 10 (that is, it is multiplied by 10), and so does the divisor! When both the dividend and the divisor are increased by the same factor, the quotient remains the same!
2. Continue the patterns,
multiplying the dividend and divisor in each step by 10, so that
3. Multiply both the dividend and the divisor by 10, repeatedly, until you
get a whole-number divisor.
The ideas in this decimals lesson are taken from Math Mammoth Decimals 2 book ($4.00 download). The book has more problems than shown in this online lesson.