Expanding and simplifying brackets

[Gringo123]

Could someone please expain where I went wrong with this?

expand and simplify the following:
1/8(6x - 12y) + 1/2(3x + 2y)

I expanded the brackets like this:
0.75x - 1.5y + 1.5x + y

and simplified like this:
2.25x - 0.5y

But the right answer is: 2.25x - 2.5y

 

[Mark44]

Your answer is correct for the problem you showed. Are you sure you copied the problem correctly? If so, the "right" answer is wrong.

 

[Gringo123]

Thanks Mark.
There must have been a misprint on the answer page of my book.
I have the same problem with this one.

1/5(15x + 10y) + 3/10(5x - 5y)

My answer is: 4.5x + 0.5y

The book says it should be: 4.5x -0.5y

Have I made a mistake or is the book wrong again?
Thanks once again for your help.

 

[Mark44]

Assuming you have written the problem as it appears in the book, your answer is correct.