The average weight of the students in a class was 45 kg. Later on, 4 students whose weights are 44 kg, 38.5 kg, 42 kg and 44.5 kg joined the class. The average weight of the students was reduced by 0.44 kg. What was the number of students, initially in the class?

26
21
20
16

LohaHridoy

12 views

2025-01-04 04:42

1 Answers

AhmedNazir

Option 2 : 21

Given:

The average weight of the students in a class was 45 kg.

Later on, 4 students whose weights are 44 kg, 38.5 kg, 42 kg and 44.5 kg joined the class.

The average weight of the students was reduced by 0.44 kg.

Concept used:

Total = Mean (Average) × number of entities

Calculation:

Let the initial number of students in the class be N.

According to the question,

45 × N + 44 + 38.5 + 42 + 44.5 = (45 - 0.44) × (N + 4)

⇒ 45N + 169 = 44.56N + 178.24

⇒ 0.44N = 9.24

⇒ N = 21

∴ The number of student initially in the class was 21.

12 views Answered 2022-09-04 04:29

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