Aptitude - Average - Discussion
Discussion Forum : Average - General Questions (Q.No. 10)
10.
In Arun's opinion, his weight is greater than 65 kg but less than 72 kg. His brother does not agree with Arun and he thinks that Arun's weight is greater than 60 kg but less than 70 kg. His mother's view is that his weight cannot be greater than 68 kg. If all are them are correct in their estimation, what is the average of different probable weights of Arun?
Answer: Option
Explanation:
Let Arun's weight by X kg.
According to Arun, 65 < X < 72
According to Arun's brother, 60 < X < 70.
According to Arun's mother, X <= 68
The values satisfying all the above conditions are 66, 67 and 68.
 Required average = |
 |
66 + 67 + 68 |  |
= | |
201 | |
= 67 kg. |
| 3 | 3 |
Discussion:
58 comments Page 2 of 6.
Minu said:
7 years ago
You can also average all 5 numbers:
60+72+68+65+70 = 335,
335/5 = 67kgs.
60+72+68+65+70 = 335,
335/5 = 67kgs.
(26)
Pankaj said:
7 years ago
Avg of least and most value is 60 + 72/2 = 66.
Her mother said not greater than 68.
So, Avg of 66 + 67 + 68/3 = 67.
Her mother said not greater than 68.
So, Avg of 66 + 67 + 68/3 = 67.
(4)
Shubham j said:
7 years ago
Arun's statement : (65+72)/2 = 68,
Arun's brother statement : (60+70)/2 = 65,
his mother statement : 68.
Now (68+65+68)/3 = 67.
Arun's brother statement : (60+70)/2 = 65,
his mother statement : 68.
Now (68+65+68)/3 = 67.
(12)
Kshitij Gupta said:
7 years ago
The answer of the question is wrong as it is based upon the assumption that the weight has integral values only which is not stated anywhere in the question.
The correct solution would be as follows:
Arun's opinion: 65-72
Brother's opinion: 60-70
mother's opinion: <68.
Therefore to find the average of the all probable weights of Arun we take the average of the lower and the upper limits:
Average of lower limits: (65+60)/2 = 62.5.
Average of upper limits: (72+70+68)/3 = 70.
Therefore the average of the possible weights of Arun would then be the middle most value of this range hence: Average of all probable weights = (62.5 + 70)/2 = 66.25 (ANS).
The correct solution would be as follows:
Arun's opinion: 65-72
Brother's opinion: 60-70
mother's opinion: <68.
Therefore to find the average of the all probable weights of Arun we take the average of the lower and the upper limits:
Average of lower limits: (65+60)/2 = 62.5.
Average of upper limits: (72+70+68)/3 = 70.
Therefore the average of the possible weights of Arun would then be the middle most value of this range hence: Average of all probable weights = (62.5 + 70)/2 = 66.25 (ANS).
(2)
Utkarsh Patil said:
7 years ago
Why did anyone not take probable weights from 65.1 to 67.9?
Yazdani said:
7 years ago
Arun's opinion between 65 to 72 kg.
So avg of Arun's opinion= 66+67+68+69+70+71÷ 6 = 68.5 --> 1
Aruns bro opinion btwetween 60 to 70kg.
Avg =61+62+63+64+65+66+69 ÷ 7 = 65 --> 2.
Arun's opinion is 68 --> 3.
Take the avg of eq 1,2,3.
We get 67.
So avg of Arun's opinion= 66+67+68+69+70+71÷ 6 = 68.5 --> 1
Aruns bro opinion btwetween 60 to 70kg.
Avg =61+62+63+64+65+66+69 ÷ 7 = 65 --> 2.
Arun's opinion is 68 --> 3.
Take the avg of eq 1,2,3.
We get 67.
Ankit said:
7 years ago
If it is greater than and less than why don't we take x+65 and x-70?
(1)
Kiran Labade said:
7 years ago
Let's Arun weight be x.
Limit in between:
1st Arun : 65 < x < 72,
2nd Brother: 60 < x < 70,
3rd Mother : 68 < = x.
Therefore, for possible values average of each approximate values
65 + 72 = 137 /2 = 68.5 (Lower Limit + Upper limit)/2,
60 + 70 = 130 / 2 = 65,
0 + 68 = 68.
Total average ages are 68.5+65+68 = 201.5.
for three limit values hence divide by three = 201.5/3 = 67.16 (float value).
we get a float value 67.16 it is complete a boundary of 67 but not a complete boundary of 68 or 69.
Hence, the approximate value of Answer is 67 kg. [A]
Limit in between:
1st Arun : 65 < x < 72,
2nd Brother: 60 < x < 70,
3rd Mother : 68 < = x.
Therefore, for possible values average of each approximate values
65 + 72 = 137 /2 = 68.5 (Lower Limit + Upper limit)/2,
60 + 70 = 130 / 2 = 65,
0 + 68 = 68.
Total average ages are 68.5+65+68 = 201.5.
for three limit values hence divide by three = 201.5/3 = 67.16 (float value).
we get a float value 67.16 it is complete a boundary of 67 but not a complete boundary of 68 or 69.
Hence, the approximate value of Answer is 67 kg. [A]
Rohit said:
8 years ago
There was not given any condition to consider weights as integer values.
Why take 66, 67 & 68 only?
Well, If he's greater than 65, And what he thinks is correct. He can weight, for instance, 65.1 or maybe 65.2.
Someone help me out here.
Why take 66, 67 & 68 only?
Well, If he's greater than 65, And what he thinks is correct. He can weight, for instance, 65.1 or maybe 65.2.
Someone help me out here.
Jaya priya said:
8 years ago
Well explained, thank you @Jasmine.
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