Question

Please explain the question with full steps.

If S is the sum of all the digits of the natural number N = 1+11+111+....... to 2011 terms, then the sum of the digits of S is
(a) 17
(b) 18
(c) 19
(d) 21

Answer 1

you can write 1 + (10+1) + (100+10+1)......

Answer 2

k

Answer 3

Now what to do ?

Answer 4

lets see

Answer 5

Yaa please

Answer 6

this has something to do with n(n+1)/2

Answer 7

the sum of the digits? as in add up all the ones?

Answer 8

ya

Answer 9

1+11+111 would equate to what; 6(1) = 6 then ? I cant tell if Im reading it right

Answer 10

a(0) = 1
a(2) = 2
a(3) = 3
a(4) = 4
.
.
.
a(n) = n
.
.
.
a(2011) = 2011

2011(2012)
----------- = number of digits? 2023066 ones then doesnt
2 sound like I understood the question :)

Answer 11

but, maybe it means: 1 + 11 + 111 = 123 = 6? thats plausible

Answer 12

1234 = 10
12345=15
123456=21
1234567=28

thats doesnt match an option either; so there needs to be more explanation as to what it is we need to accomplish

Answer 13

Yes please help ?

Answer 14

Yes please help ?

Answer 15

Now will you please explain with steps

Answer 16

Yes please help ?

Answer 17

Will you please check what I am doing is right or not /

Answer 18

Yes please help ?

Answer 19

And median is what uber has told :)