The average weight of Mukund, Sachin and Chetan is 46 kg. If the average weight of Mukund and Sachin be 39 kg and that of Sachin and Chetan be 45 kg, then the weight of Sachin (in kg) is:

Correct option is D

Given:

Average weight of Mukund, Sachin and Chetan = 46 kg
Average weight of Mukund and Sachin = 39 kg
Average weight of Sachin and Chetan = 45 kg
Formula Used:
Sum =Average×Number of persons
Solution:
Total weight of Mukund, Sachin, and Chetan = 46 × 3 = 138 kg
Total weight of Mukund and Sachin = 39 × 2 = 78 kg
Total weight of Sachin and Chetan = 45 × 2 = 90 kg
Weight of Sachin = (78 + 90 - 138) = 30 kg