Texas
Rule Out Extra Information
Rule out information that is not needed to solve the problem.
Now we should reread each sentence to look for the information that we need to find the answer. Let's start with the first sentence.
There are 9 birds. Three are red. Four fly away. How birds are left?
This sentence tells us there were 9 birds at first. We need to know the number of birds there were to find the answer.
