Answer:
182 1/3 lbs
Explanation:
If you don't want to mess with adding and subtracting obscure fractions, you can let your calculator do it.
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I find it convenient to add the integer parts separately from the fractional part. Usually, only a slight adjustment is needed at the end.
Integer parts:
... 170 +25 -10 -3 = 182
Fractional parts:
... 2/3 +5/12 -1/4 -1/2 = (8 +5 -3 -6)/12 = 4/12 = 1/3 (added to the above)
Weight after 2 weeks of practice: 182 1/3 lbs.