Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
0 votes

How many 10 digit numbers are there using the digits 1 and 2 ?

$\begin{array}{1 1} (A)\;^{10}C_1+^9C_1 \\ (B) \;2^{10} \\ (C) ^{10}C_2 \\ (D) 10! \end{array}$

Can you answer this question?

1 Answer

0 votes
Each place can be fixed by any of the two digits.
$\therefore$The required 10 digit numbers = $2^{10}$
answered Aug 15, 2013 by rvidyagovindarajan_1

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App