Solved UPSC CDS/OTA Question
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Q · LogarithmMedium · 45s
If log₂ = .301, log₃ = .477, find the number of digits in (108)10.
TopicLogarithm
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained - no skipped algebra.
Let the number be y,
Y = 10810
⇒logy = 10log 108
logy = 10log (27 × 4)
logy = 10[3log₃ + 2log₂]
logy = 10[1.43 + 0.602]
Hence logy = 10[2.03] = 20.3
Thus, y has 21 digits
Final Answer: Option B - 27