Re: If 20/5 = 1/2^m + 1/2^n what is nm ?
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22 Nov 2021, 03:38
\(\frac{20}{2^5} = \frac{4*5}{2^5} = \frac{2^2*5}{2^5} = \frac{5}{2^{5-2}} = \frac{5}{2^3} = \frac{4+1}{2^3}\)
\(\frac{4+1}{2^3} = \frac{4}{2^3} + \frac{1}{2^3} = \frac{2^2}{2^3} + \frac{1}{2^3} = \frac{1}{2^1} + \frac{1}{2^3} = \frac{1}{2^m} + \frac{1}{2^n}\)
Therefore, \(m = 1\) and \(n = 3\)
\(nm = 3*1 = \textbf{3}\)
Hence, Answer is B