Math puzzles are a great way to engage students in developing critical thinking skills. This math puzzle is an educational activity for practicing children’s math skills.
Challenge:
The average of five numbers is 11 and the average of eight numbers is 7.75. What is the average of these 13 numbers?
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The correct answer is 9.
The average of five numbers is 11. Therefore, their sum is:
5 × 11 = 55
The average of eight numbers is 7.75. Therefore, their sum is:
8 × 7.75 = 62
The sum of all 13 numbers is 55 + 62 = 117
Therefore, the average of these 13 numbers is:
117 ÷ 13 = 9
