Mathematics Problem Solving 1

Ryan’s Class
There are exactly twelve children in Ryan’s class. Only four of the children are boys. The following questions refer to a time when all the children are present in the class. There are no visitors in the class. There might be more than one correct anwer to a question.

1. Which of the lettered statements must be true?
2. Which of the lettered statements cannot be true?
3. Which of the lettered statements could be true or not true?

a. There are twice as many girls as boys in Ryan’s class.
b. There are eight more girls than boys in Ryan’s class.
c. There are four more girls than boys in Ryan’s class.
d. If Ryan is sitting at a table with all the girls, there are exactly nine children at that table.
e. If only three of the boys are standing on their heads, one of the boys is not standing on his head.





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