Bihar Police Constable Model Paper 3

Given:
12 articles at each = 40
15 articles at each = 60
13 articles at each = 40
Concept:
Average = Total amount / Total articles
Solution:
Total amount = (12 × 40) + (15 × 60) + (13 × 40)
⇒ 480 + 900 + 520
⇒ 1,900
Total articles = 12 + 15 + 13 = 40
∴ Average = 1,900 / 40 = 47.5