Latest TCS Aptitude Question SOLUTION: 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 In which row 2015 would come?

• Placement Papers
• /
• TCS
• /
• Numerical Ability
• /
• Arithmetic

TCS Question Papers: TCS Interview Experience(90) TCS Company Profile

(#M40155047) TCS Numerical Ability question Number System Keep an EYE

1
3 5
7 9 11
13 15 17 19
21 23 25 27 29
In which row 2015 would come?

Asked In TCS Devendra Kumar (8 years ago)

Unsolved Read Solution (11)

Is this Puzzle helpful?   (16)   (2) Submit Your Solution Arithmetic

Read Solution (11) :

RAKESH G.N  (8 years ago)

1
3 5 consider last element in this row 5 which is (row number)^2+1=(2)^2+1=5
7 9 11 similarly, 11 (row number)^2+1=(3)^2+2=11
13 15 17 19 similarly, 19 (row number)^2+1=(4)^2+3=19
21 23 25 27 29 similarly, 29 (row number)^2+1=(5)^2+4=29

consider 44th row=(44)^2+43=Last element is1979.So, 2015 can't be in this row.
consider 45th row=(45)^2+44=Last element is 2069.So, 2015 will be in this row.

So, 2015 will be in 45th row.

Is this solution Helpfull? Yes (43) | No   

Rishu  (8 years ago)

45th row

let the total number of digits be n
then 2015=1+(n-1)2 or n=1006

let 2015 comes in 'm' th row
now, 1st row contains 1 digit, 2nd row contains 2 digits, 3rd row contains 3 digits and so on
and also sum of all digits in rows from 1 to m is 1008
in other words 1008 is the sum of first m natural numbers
therefore,
m(1+m)/2=1008
m^2+m-2016=0
m=44.4
so, 2015 comes in a row which is just after 44th row, i.e.,45th row

Is this solution Helpfull? Yes (5) | No   

manikandan  (8 years ago)

n(n+1)/2 gives 44*45/2=990...then 1+(990-1)*2=1979 is the starting element..the row ll hold 1979+44 elements..so its on 44th row..

Is this solution Helpfull? Yes (1) | No (2)  

manikandan  (8 years ago)

1979 s the last element sry guys....the nezt row 45th l contain 45 elements..so 2015 i in 45th row

Is this solution Helpfull? Yes (1) | No (2)  

priyadharshini  (8 years ago)

Ans is 45th row

Is this solution Helpfull? Yes (1) | No (2)  

Deepak kumar singh  (8 years ago)

45 is rt answer

Is this solution Helpfull? Yes (1) | No (2)  

shubham singh  (8 years ago)

i think ans should be 15

Is this solution Helpfull? Yes | No (3)  

shubham singh  (8 years ago)

typing error sorry it should be 14.

Is this solution Helpfull? Yes | No (3)  

Sourabh Prasad  (8 years ago)

All options of answers of this Question are more than 44.

Is this solution Helpfull? Yes | No (3)  

Tani Verma  (8 years ago)

mene 44 tick kiya and dnt knw its right or wrong

Is this solution Helpfull? Yes | No (3)  

Divya Batra  (6 years ago)

answer is 45th row.

Is this solution Helpfull? Yes | No   

Please Login to Read Solution.