Hello wolfhoundYour answer isn't wrong - it just isn't in its lowest terms. In other words, it will cancel - and it cancels to the correct answer: .

The reason you didn't get it in its lowest terms is that you didn't find the lowest common denominator. The denominators are:andand the lowest common denominator is simply . So when you're combining the two fractions, you don't need to change the second one at all. You get this:Do you see how it works?

Grandad