Question 425762
a)How do I find the arithmetic mean of: 
i) 9 and 21
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Ans: (9+21)/2 = 10
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ii) 6+sqrt(3) and 6-sqrt(3)
Ans: Add and divide by 2 to get 6
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b) Insert 5 arithmetic means between 11 and 71.
a(1) = 5
a(6) = a(1) + 6d = 71
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Solve for "d":
5 + 6d = 71
6d = 66
d = 11
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Sequence: 5,16,27,38,49,60,71
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Cheers,
Stan H.
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