there are 4 unknown numbers the mean of first 2 numbers is 4 and the mean of first three is 9 the mean of all 4 numbers is 15 if one of the four numbers. is 2 find the other numbers
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Mean of 4 numbers = 15
Sum of these 4 numbers = 15 × 4 = 60
Mean of first 2 numbers = 2
Then, sum of these 2 numbers = 2 × 4 = 8
Mean of these 3 numbers = 9
Then, sum of these 3 numbers = 9 × 3 = 27
Then the 3rd number = 27 - 8 = 19
Then the fourth number = Mean of all 4 numbers - mean of first three numbers = 60 - 27 = 33
2 is one of the all four number which is given in the question.
Now, we have
2 (given), 33 (which is the 4th number) and 19 (which is the 3rd number)
Then the remaining number is:-
60 - (2 + 33 + 19)
60 - 54 = 6
The remaining numbers other than 2 are 6, 19 and 33.
Sum of these 4 numbers = 15 × 4 = 60
Mean of first 2 numbers = 2
Then, sum of these 2 numbers = 2 × 4 = 8
Mean of these 3 numbers = 9
Then, sum of these 3 numbers = 9 × 3 = 27
Then the 3rd number = 27 - 8 = 19
Then the fourth number = Mean of all 4 numbers - mean of first three numbers = 60 - 27 = 33
2 is one of the all four number which is given in the question.
Now, we have
2 (given), 33 (which is the 4th number) and 19 (which is the 3rd number)
Then the remaining number is:-
60 - (2 + 33 + 19)
60 - 54 = 6
The remaining numbers other than 2 are 6, 19 and 33.
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