CMA Foundation · Fundamentals of Business Mathematics and Statistics · Indices and Logarithms
Using log 2 = 0.3010, how many digits does 2^40 have?
The log of 2 to the power 40 is 40 times 0.3010, which is 12.04. The number of digits is the characteristic plus one, so 2^40 has 13 digits.
- A12Correct
- B13
- C11
- D14
Explanation
log 2^40 = 40 × 0.3010 = 12.04. The characteristic is 12, so the number of digits is 12 + 1 = 13. Therefore the correct count is 13, not 12 (which forgets to add 1).
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