Multiple choice

The average weight of 25 students in a class is 48 kg. When the weight of the teacher is also included, the average increases by 1 kg. What is the weight of the teacher?

  1. 75 kg

  2. 74 kg

  3. 73 kg

  4. 70 kg

  5. 80 kg
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Total weight of 25 students = 25 * 48 = 1200. With teacher, total people = 26, average = 49. Total weight = 26 * 49 = 1274. Teacher's weight = 1274 - 1200 = 74 kg.

AI explanation

The total weight of the 25 students is 25 times 48, which equals 1200 kg. When the teacher is included, the new average is 49 kg for 26 people, making the new total weight 26 times 49, which equals 1274 kg. The teacher's weight is the difference between the new total and the old total, so 1274 minus 1200 equals 74 kg.

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