# Math Help - Fration help

1. ## Fration help

I hoping somone will help me understand why I'm getting the wrong answer to this problem

Negetive sixty five sevenths divided by thirteen.
-65/7 \13
My answer is -65/91 Negetive sixty five ninety ones.

2. Originally Posted by Gerry
I hoping somone will help me understand why I'm getting the wrong answer to this problem

Negetive sixty five sevenths divided by thirteen.
-65/7 \13
My answer is -67/91 Negetive sixty seven ninety ones.
Hello,

you are supposed to know that every (integer) number can be written as a fraction: $13 = \frac{13}{1}$

With this property your division becomes:

$-\frac{65}{7} \div 13 = -\frac{\frac{65}{7}}{\frac{13}{1}} = -\frac{\not{6}\not{5}^5}{7} \cdot \frac{1}{\not{1}\not{3}_1} = -\frac57$

3. ## canceling

My problem is the canceling I guess.

I knew to take the recipricole of 13 and change the operation to Multiplication. Then I just thought you multiply the Numerators and Denominators across.

when you have the problem set up as:

65/7 x 1/13 =

are you supposed to cross divide?

4. Originally Posted by Gerry
My problem is the canceling I guess.

I knew to take the recipricole of 13 and change the operation to Multiplication. Then I just thought you multiply the Numerators and Denominators across.

when you have the problem set up as:

65/7 x 1/13 =

are you supposed to cross divide?

"Cross divide?" Never heard of it. But perhaps doing it in this format will help:
$\frac{65}{7} \times \frac{1}{13} = \frac{65}{7 \cdot 13}$

$= \frac{5 \cdot 13}{7 \cdot 13} = \frac{5}{7}$

-Dan

5. Hello, Gerry!

Don't kick yourself too hard . . .

Negetive sixty five sevenths divided by thirteen.
-65/7 \13