Question 1039515
Sn=[2(1/5)+(12-1)-1/2
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Note: you did not close the bracket pair.
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Sn = [(2/5) + 11 - 1/2]
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Sn = (4/10 + 110/10 - 5/10]
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Sn = 109/10
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Sn = 10.9
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Cheers,
Stan H.
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