Adding Fractions

[Futurebrewing]

Hello all.

I am having trouble with this math problem.

-7/10 + 11/90

Here is what I am coming up with:

the lowest common denominator is 90 so I get:

-63/90 + 11/90

My answer is:

-52/90

What am I doing wrong? The answer in the back of my math book is:

-26/45

I would greatly appreciate any information you may have for me. Thank you for your time.

 

[Denis]

My answer is:
-52/90
What am I doing wrong? The answer in the back of my math book is:
-26/45

Those are EQUAL; same way as 2/4 = 1/2 :idea:

 

[Ryan Rigdon]

thats right. always try to reduce your answers if you can.