Given log₁₀2 = 0.3010, evaluate log₁₀80.
Aptitude
Logarithm
Difficulty: Easy
Choose an option
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A1.6020
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B1.9030
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C1.6990
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D2.0792
Answer
Correct Answer: 1.9030
Explanation
Concept / Approach
- Factorize 80 = 8 × 10 = 2 3 × 10 80=8×10=2 3 ×10.
- Use log rules: log ( 𝑎 𝑏 ) = log 𝑎 + log 𝑏 log(ab)=loga+logb, log ( 2 3 ) = 3 log 2 log(2 3 )=3log2.
Step-by-step calculation log 10 80 = log 10 ( 2 3 ) + log 10 10 = 3 log 10 2 + 1 log 10 80=log 10 (2 3 )+log 10 10=3log 10 2+1 = 3 ( 0.3010 ) + 1 = 0.9030 + 1 = < 𝑚 𝑎 𝑟 𝑘 > 1.9030 < / 𝑚 𝑎 𝑟 𝑘 > =3(0.3010)+1=0.9030+1=1.9030
Quick checkSince 80<100, log 10 80 log 10 80 should be just under 2; 1.9030 is reasonable.
Final Answer1.9030