Parit's Doubt...
Three boxes of supplies have an average(arithmetic mean) weight of 7 kilograms and a median weight of 9kg. What is the max possible weight, in kg, of the lightest box?
A. 1
B. 2
C. 3
D. 4
E. 5
Solution:
The total of three boxes = 7x3 = 21kg
The middle box =9kg and thus, the other two weight 21-9 = 12 kg together.
The heaviest box has to weight at least 9 kg.
Thus, the max weight of the lightest box = 12-9 = 3 kg
The mistakes you must have committed is to assume the heaviest box to weigh more than 9; ie 10. It can as well weight 9 and the median of the set shall still be 9.
Regards,
Maxximus
Three boxes of supplies have an average(arithmetic mean) weight of 7 kilograms and a median weight of 9kg. What is the max possible weight, in kg, of the lightest box?
A. 1
B. 2
C. 3
D. 4
E. 5
Solution:
The total of three boxes = 7x3 = 21kg
The middle box =9kg and thus, the other two weight 21-9 = 12 kg together.
The heaviest box has to weight at least 9 kg.
Thus, the max weight of the lightest box = 12-9 = 3 kg
The mistakes you must have committed is to assume the heaviest box to weigh more than 9; ie 10. It can as well weight 9 and the median of the set shall still be 9.
Regards,
Maxximus
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