NECO 2022 · Paper 1 · Q8

Given that $\log 2 = 0.30103$ and $\log 3 = 0.47712$ , calculate without using tables: $\log 6 - \log 0.3$ .

Worked solution (try it first)

Subtracting logs divides the numbers: $\log 6 - \log 0.3 = \log \dfrac{6}{0.3}$ .
$\dfrac{6}{0.3} = 20$ , and $\log 20 = \log 2 + \log 10$ .
$\log 10 = 1$ , so the value is $0.30103 + 1 = 1.30103$ , option E.