Thursday, January 30, 2014

Predicting Products. Homework Help 7.5

When you predict products there are a few things you can remember.

If you have a whole number (like 4, or 8 or 2 or 34,234) and you times that by a fraction (2/3 or 5/7 or 2/10) you will get a number that is SMALLER than the whole number (smaller than 4, smaller than 8 or smaller than 32,234).   BUT your answer WILL be greater than the fraction (greater than 2/3, greater than 5/7 and greater than 2/10)  So in a sense your whole number and your fraction meet together on a number line.  The fraction gets bigger and the whole number gets smaller.  And where they meet is your product (answer).

For example:
3/4  x 7= 5 1/4  (5 1/4 is bigger than 3/4  AND  5  1/4 is smaller than 7)  It's in between the two factors.
another example....
7/12  x 8 = 4 2/3   (4  2/3 is bigger than 7/12 and smaller than 8)
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What about a FRACTION X FRACTION?
If you have a fraction (1/2 or 3/7 or 9/12) and you TIMES that by a fraction (1/2 or 3/7 or 9/12) you will get an answer (or product) that is LESS THAN both of the fractions.    You can think of it this way.  If I eat 1/2 of my candy bar what is left?  1/2 right?  But then Porter comes along and eats another 1/4 of that?  What's left?  An even SMALLER amount of candy bar.  So 1/2 times 1/4 is something smaller than both 1/2 and 1/4.

For example:
9/10  x  2/3  = 9/15

9/15 is smaller than 9/10 AND
9/15 is smaller than 2/3

So any FRACTION X FRACTION will always = an answer that is LESS THAN both fractions.
Little fraction times a little fractions equals an even littler fraction

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