My Maths tidy numbers

For maths my group had to do some tidy numbers and we did some problems. Our follow up was to do two word problems. My first problem is 385+488=?  I am going to solve it by using tidy numbers.

So I did was 385+488=?. So now what I did was 385-2=383 and now 488+2=490. 383+490=873.

Now I am working this problem. If I got 792 then I lost 674 dollars now using tidy numbers it will be 792-6=786. Then 674+6=680 so now it is now 786-680=106.

Here is one for you to try 865+139= 

See if you can use tidy numbers.