3: Take 1000. Add 40. Add another 1000.
Add 30. 1000 again. Plus 20.
Plus 1000. And plus 10.
What is the total?
Ans is 2030 for total.
Why, first is 1000+40+1000+30=2070.
Then another sum which is 1000+20+1000+10=2030.
For me I will take the second sum as final answer as it should overwrite the first sum.
Tactical solution is if ones can't convince then confuse