61-34x98+90+21-4
We will put these in parenthesis to make it easier to read, and to mark what needs done first.
61-(34x98)+90+21-4
34x98=3,332
Now that the multiplication is done, we add and subtract.
90+21=111
61-3,332=-3271
-3271+111-4
We can reorder this to make it easier. Plus, we'll subtract -4 and -3271.
111-3275=-3164
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sorry if this doesn't help