Multiple choice

The average weight of 31 students in a class is 40 kg. If the weight of the teacher is included, the average weight increases by 0.25 kg. Find the weight of the teacher.

  1. 52 kg

  2. 48 kg

  3. 50 kg

  4. 55 kg

  5. 53 kg

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Original average weight of (A) = 46 kg

Original number of candidates (N) = 31

Increase in average weight (d) = 0.25 kg

Now, apply the following shortcut formula:

Weight of the teacher = A + (N + 1 )d

= 46 + (31 + 1) * 0.25 

= 48 kg