0 votes 0 votes All the page numbers from a book are added, beginning at page $1.$ However, one page number was mistakenly added twice. The sum obtained was $1000.$ Which page number was added twice? $44$ $45$ $10$ $12$ Quantitative Aptitude cat2001 quantitative-aptitude number-systems + – go_editor asked Mar 31, 2016 edited Apr 10, 2022 by Lakshman Bhaiya go_editor 13.8k points 672 views answer comment Share See all 0 reply Please log in or register to add a comment.
0 votes 0 votes Let Number of pages=n The sum of all the page numbers = $\frac{n(n+1)}{2}$ We can quite easily see that for n=44, we have the sum as $\frac{44*45}{2}$ = 22*45 = 990. Thus, the page number 10 must have been added twice. Hence (3)10 is the Answer. Leen Sharma answered May 8, 2016 Leen Sharma 11.5k points comment Share See all 0 reply Please log in or register to add a comment.