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Problem 3: A class has 45 students, including both boys and girls.

• There are 15 girls in the class.
• The number of boys is 7 more than the number of girls.
  • a) Find the number of girls in the class.
  • b) Find the number of boys in the class.

Problem 4: A class has 45 students, including both boys and girls.

• If 10 boys are added to the class, the number of boys will become equal to the number of girls.

Problem 5: A class has 45 students. Find how many boys and how many girls are in the class.

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