

InterviewSolution
Saved Bookmarks
1. |
Consider the pattern shown below: `{:(" Row ",1,1,,,),(" Row ",2,3,5,,),(" Row ",3,7,9,11,),(" Row ",4,13,15,17,19):}etc.` The number at the end of row 60 isA. 3659B. 3519C. 3681D. 3731 |
Answer» Correct Answer - A If last term of nth row is `T_(n)`, then Let `S=1+5+11+19+"...."T_(n)` `(S=ul1+ul5+ul11+ul19+"....+"ulT_(n-1)+ulT_(n))/(0=1+4+6+8"....."n" terms "-T_(n))` `T_(n)=1+2(2+3+4+"....."(n-1)" terms" )` ,brgt `=1+2((n-1))/(2)[2*2+(n-2)*1]` `=1+(n+1)(n+2)` `=1+n^(2)+n-2` `implies T_(n)= n^(2)+n-1` `:. T_(60)=(60)^(2)+60-1=3600+59=3659`. |
|