Let's assume you have supplement angle

Now when you talk about multiplication you can simply say...

And that will give you the answer.
Erm i could you explain more of the question we can't go by just this
The answer is 7 you have to add 19 and 15 together and when you get the answer subtract that from 41 and you get 7
221.57
Explanation:
To round to the nearest tenth you would would look at the hundredths place. If it is higher than 5 you round the number in the tenth place up if it is lower than 5 you keep it the number in the tenth place the same. In this case you have 2 which is lower than 5 so you keep the 7 the same and bring everything else down.
I think you have to multiply across.