If $\log_{10} 2 = 0.3010$, then $\log_{2} 10$ is equal to
Aptitude
Logarithm
Difficulty: Easy
Choose an option
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A$\frac{699}{301}$
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B$\frac{1000}{301}$
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C0.3010
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D0.6990
Answer
Correct Answer: $\frac{1000}{301}$
Explanation
### Concept & Formula
This problem directly tests your knowledge of the Base-Switching property of logarithms.
If you swap the base and the argument of a logarithm, the new logarithmic value is simply the mathematical reciprocal of the original value.
Formula: $\log_a b = \frac{1}{\log_b a}$
### Step-by-Step Solution
Given the equation:
$$ \log_{10} 2 = 0.3010 $$
Step 1: Apply the base-switching rule to find $\log_{2} 10$.
$$ \log_{2} 10 = \frac{1}{\log_{10} 2} $$
Step 2: Substitute the known numerical value into the denominator.
$$ \log_{2} 10 = \frac{1}{0.3010} $$
Step 3: Convert the decimal into a fraction to match the provided multiple-choice options.
Since $0.3010$ can be written as $\frac{3010}{10000}$ or $\frac{301}{1000}$:
$$ \log_{2} 10 = \frac{1}{\frac{301}{1000}} $$
Step 4: Simplify the complex fraction by flipping the denominator.
$$ \log_{2} 10 = \frac{1000}{301} $$
### Exam Strategy & Shortcut
**Reciprocal Decimal Recognition:** When you see the base and argument flipped, immediately know you just need the reciprocal: $1 / 0.3010$.
To calculate quickly without a calculator, ignore the decimal places temporarily. You know you are doing $1$ divided by roughly $3/10$, so the answer must be around $10/3$. Looking at the options, $\frac{1000}{301}$ is the exact fractional representation of this reciprocal.
### Common Pitfall
Students often get confused by the zeros in the decimal and select an incorrectly scaled fraction like $\frac{100}{301}$ or mistakenly attempt to use subtraction rules. Keep your decimal places aligned when converting to a fraction: $0.301 = 301/1000$.
### Final Answer
**Therefore, the correct answer is $\frac{1000}{301}$.**