1. You have to look at the problem first.
2. Choose what type of operations you are going to use.
3. Choose which set of numbers you should answer first.
4. Do the solving.
5. Recheck if you have that gut feeling that it is wrong.
6. Simplify answer (if necessary)
7. Pray that your answer is correct.
8. proceed to the next question (if there is one)
9. repeat steps 1 - 8 until finished
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We can solve the problem solving if we analyze and understand the problem. 
Don't also forget to use your common sense especially in solving problems in mathematics and some experiments.
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