Question

If $\log _{10} 2=0.301 \& \log _{10} 3=0.477$, then the number of digits in the number $N =3^{12} \times 2^8$ is equal to

• A. 9
• B. 8
• C. 7
• D. 5

Answer 1

Answer: (A)

$N =3^{12} \times 2^8$
$\log _{10} N =12 \log _{10} 3+8 \log _{10} 2 $
$ =12 \times 0.477+8 \times 0.301$
$ =5.724+2.408$
$\text { char }=8 \therefore \text { number of digits }=9$