The division of whole numbers by fractions seems to be confusing to many people - even to some forum members!!! And I can see why.......

Yesterday....we had this problem.......

48 divided by -6/7

We are taught the "order of operations" thing, so it seems "logical" to apply it here.....that is....

Evaluate 48/-6, first = -8

Then, divide this result by 7 = -1.1428571428571429

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To keep from making this mistake, remember to "convert" the "48" to (48/1) so that we have....

(48/1) /(-6/7) ...and now apply the "KEEP" "CHANGE" "FLIP" rule.....

"KEEP" the first fraction.... (48/1)

"CHANGE" the division to multiplication

"FLIP" the second fraction (-6/7) → (7/-6)

So we have.....

(48/1) * (7/-6) =

(48/-6) * (7/1) =

-8 * 7 =

-56

Notice how, in the second step, I "exchanged" denominators......we can often do this in the multiplication of fractions in order to make the "cancelling" easier. Note...this will * NOT* work with the addition, subtraction or division of fractions!!! Be careful!!!!

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As one final word....note that when we divide a whole number by something that has an absolute value greater than 0, but less than 1, that we * have* to end up with a result that has an absolute value greater than the absolute value of the whole number itself!!!

Hope this helps !!!!

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As an edit...also remember that dividing things having the same signs results in a positive, while dividing things with different signs results in a negative....just like the rules for multiplication!!!

CPhill
Aug 3, 2014

#1**+3 **

Thanks for that CPhill!its really helps..................that question was getting confusing slowly and slowly yntil i found the mystery..........................poor Zegroes wasnt interested in the Treasure Hunt and just ran away .................and even lost the match!!!

i know i know .......you are reallly sad after losing the game Zegroes.....

but dont be sad like this,...................................................................that problem was not a big deal!

rosala
Aug 3, 2014

#3**+8 **

OOps sorry!i should have said Answer Hunt!

But treasure or answer , not much difference though!

But whatever it is , i just know (u too know) , that u lost it!

rosala
Aug 3, 2014

#4**+8 **

Best Answer

Great explanation CPhill. Thanks for clearing that up for everyone.

I'm going to go ahead and add this post to the "Reference Material" thread. I think this post should fit well there!

NinjaDevo
Aug 4, 2014