Question

The mean weight per student in a group of 7 students is 55 kg. The individual weights of 6 of them (in kg) are 52, 54, 55, 53, 56 and 54. Find the weight of the seventh student.

Answer 1

The mean weight per student in a group of 7 students = 55 kg

Weight of 6 students (in kg) = 52, 54, 55, 53, 56 and 54

Let weight of 7^th student = x kg

Therefore, Mean \(=\frac{Sum\, of \,all \,\text{w}eights}{Total\,students}\)

 \(55=\frac{52 + 54 + 55 + 53 + 56 + 54 + x}{7}\)

\(385=324 + x\)

x = 385 – 324

x = 61 kg

Therefore, weight of 7^th student = 61 kg