Thu - November 6, 2003

Fractions



Yours is not to wonder why,
Just invert and multiply.

Or, on the other hand, you could spend a few minutes wondering about what is happening when you divide by a fraction. Memorizing algorithms, with no understanding, often leads people to feel dumb and that can build up into math avoidance, math anxiety, or math phobia.

Start with 2 divided by 2/3. Think of it as 2 cups of pudding divided into servings that are 2/3 cups each. How many servings will you have? Take 2/3 out of each of the cups of pudding - that's 2 servings. Each of the cups has 1/3 left in it - so that is two more thirds or another 2/3. So - 2 cups breaks down into 3 servings that are 2/3 cups each. 2 divided by 2/3 is 3 because 2 cups of pudding divided into 2/3 cup servings yields 3 servings.

Think a bit about 6/8 of a pizza and imagine dividing it into 3 pieces. You can think of that 6/8 of a pizza as 2/8 and 2/8 and 2/8, so each of the 3 pieces is 2/8. So 6/8 divided by 3 equals 2/8.

Now think about it just a little differently - imagine dividing 6/8 of a pizza into pieces so that each piece is 2/8, how many pieces would you have? Three. So 6/8 divided by 2/8 equals 3.

Posted at 02:36 PM     Read More  

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