Question

If log2 base10 =0.3010, the value of log5 base10 is

Answer 1

log(2) = 0.3010
log(1/2) = log(1) - log(2) = 0 - 0.301
log(0.5) = - 0.301
log(5) = log(0.5*10) = log(0.5) + log(10) = 0.699

Answer 2

$log_{10} 2 =0.3010$
Now, 
$log_{10} 5$
$log_{10} 5 = log_{10} ( \frac{10}{2})$
$log_{10} 5 = log_{10} 10 - log_{10} 2$

$log_{10} 5 = 1 - 0.3010$

$log_{10} 5 = 0.699$