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shivam_bhalla
A simple looking tough question pertaining to number of digits. Question below
5^30=(10/2)^30=p(say) now log p =log 10^30 - log 2^30 = 30-30*.3010=20.97 so 5^30 lies between 10^20 and 10^21.. so it has 21 digits
Thanks @1729antony , good work brother. Dunno where I left my brain today :P