A math puzzle for smart people with a brain for math! This challenge is for those who love to be challenged by mathematics and critical thinking problems. Let’s challenge your brain!
Challenge:
If \(a = (5^{11})^{2}\) and \(b = 4^{11}\), how many digits long is ab?
A- 22
B- 23
C- 33
D- 44
E- 121
The Absolute Best Book to challenge your Smart Student!
The correct answer is B.
\(a = (511)^{2} = 5^{22}\) and \(b = 4^{11}\)
Change the base of number b from 4 to 2: \(b = 2^{22 }\)
Therefore, \(ab = 5^{22} × 2^{22 }= 10^{22}\)
Number \(10^{1}\) has 2 digits and number \(10^{2} (100)\) has 3 digits. Therefore, \(10^{22}\) has 23 digits.
