(a)(i) Given that \(\log_{10} 5 = 0.699\) and \(\log_{10} 3 = 0.477\), find \(\log_{10} 45\), without using Mathematical tables.
(ii) Hence, solve \(x^{0.8265} = 45\).
(b) Use Mathematical tables to evaluate \(\sqrt{\frac{2.067}{0.0348 \times 0.538}}\)
Verified Correct Answer: .
Step-by-Step Mathematical Solution
(a)(i) \(\log_{10} 45 = \log_{10} (3 \times 3 \times 5)\)
= \(\log_{10} (3^{2} \times 5)\)
= \(\log_{10} 3^{2} + \log_{10} 5\)
= \(2 \log_{10} 3 + \log_{10} 5\)
= \(2(0.477) + 0.699\)
= \(0.954 + 0.699 = 1.653\)
(ii) \(x^{0.8265} = 45\)
Taking the log of both sides,
\(\log_{10} x^{0.8265} = \log_{10} 45\)
\(0.8265 \log_{10} x = \log_{10} 45\)
\(\log_{10} x = \frac{1.653}{0.8265}\)
\(\log_{10} x = 2\)
\(x = 10^{2} = 100\)
(b) \(\sqrt{\frac{2.067}{0.0348 \times 0.538}}\)
No
Log
2.067
\(0.0348\) = 0.3513 -
0.0348
\(\bar{2}.5416 +\)
0.538
\(\bar{1}.7308\)
\(\bar{2}.2724\) = \(\bar{2}.2724\)
= \(2.0789 \div 2 = 1.0395\)
Antilog - 10.95
\(\therefore \sqrt{\frac{2.067}{0.0348 \times 0.538}} = 10.95\)
Source: Myschool Past Questions Archive (Record #54570)