10
14
27
28
Correct answer is B
log2 4 + log2 7 - log2 n = 1
= log2 (4 x 7) - log2 n = 1
∴ log_2 28 - log_2 n = 1
= \frac{28}{n} = 2^1
\frac{28}{n} = 2
2n = 28
∴ n = 14
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