SOLUTION: X/1 2 3 4 5 6 F/4 6 a 10 b 8 The mean of 50 observations for a grouped data is 3.72 the two frequencies are missing in the frequency table.find the missing frequencies..

Algebra ->  Probability-and-statistics -> SOLUTION: X/1 2 3 4 5 6 F/4 6 a 10 b 8 The mean of 50 observations for a grouped data is 3.72 the two frequencies are missing in the frequency table.find the missing frequencies..       Log On


   

Question 752709: X/1 2 3 4 5 6
F/4 6 a 10 b 8
The mean of 50 observations for a grouped data is 3.72 the two frequencies are missing in the frequency table.find the missing frequencies..
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
X/1 2 3 4 5 6
F/4 6 a 10 b 8
The mean of 50 observations for a grouped data is 3.72 the two frequencies are missing in the frequency table.find the missing frequencies..
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mean = [1*4+2*6+3a+4*10+5b+6*8]/50
[4+12+3a+40+5b+48]/50 = 3.72
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[3a+5b+104] = 186
3a+5b = 82
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Sum of the frequencies = 50
a+b + 28 = 50
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Using the 2 equations, solve for "a" and for "b":
3a+5b = 82
a + b = 22
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Modify for elimination:
3a + 5b = 82
3a + 3b = 66
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Subtract and solve for "b":
2b = 16
b = 8
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Solve for "a":
a + 8 = 22
a = 14
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Cheers,
Stan H.
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