If one writes a list of integers from 1 to 1000, then how

Question

If one writes a list of integers from 1 to 1000, then how many zeroes will there be on the list?

mba · Answer

191

Consider numbers as
X - 0 (No zeros for this digit)
XX - 9(Total 9 times zero will appear)
XXX - 90(Zero at tens place)+90(Zero at units place) - 1(common case when 0 apears both at tens and units place) = 179
1000 = 3

bigtooth81 · Answer

147?

0 as unit --> 9 possibilities for tenth & 8 possibilities for huns -->72 possibilities
0 as tenth --> 72 possibilities

72 + 72 + 3(for 1000) = 147

sathya76 · Answer

Two digit Numbers (9)(1) =9

Three digit Numbers (9)(10)(1) + (9)(1)(10) = 180

For 1000 ==> 3

Ans : 192

sid_477 · Answer

ok i might have a different soln

1-100
(10,20,30,40,50,60,70,80,90,100) = 11zeros

1-900 ==> 11 x 9 = 99 zeros

900-1000 ==> 12 zeros
101-109= 9 zeros
201...301...= 9x9 = 81 zeros

99+12+81=192zeros

mba · Answer

Stolyar: What's the OA,

(Also If I am wrong, can anybody point out the mistake.)

ashkg · Answer

I had made the same mistake in challenge 1 what you have done above.
Since this question is asking how many times 0 is listed we have to account for each 0 that appears.

X00 has 2 zeros. If you remove the common case you will be counting this number only once, but we are not supposed to count the number. We are supposed to count the number zeroes.

X00 as 2 zeros and should be counted twice. 192 should be the correct answer.

- ash

mba · Answer

Thanks! ashkg? :oops:

DaveforMBA · Answer

I liked this answer
Two digit Numbers (9)(1) =9 

Three digit Numbers (9)(10)(1) + (9)(1)(10) = 180 

For 1000 ==> 3 

Ans : 192

But, What do
(9)(10)(1) represent

and
 (9)(1)(10)

K_s_r · Answer

1- 99 = 9

100 - 199 = 100 -110 + till 190 = 12 + 8

100 - 990 = 20 * 9 = 180

1000 = 3

---------------

 192

--------------------

anuramm · Answer

I feel that the answer has to be 183 because -

1 - 9 = 0
10 - 99 = 9
100 - 999 = 171 = 9 * 10 *1 + 9 * 1 *10 - 9 ( -9 because we are accounting for 0 in the tenth and unit place twice for nine combinations)
1000 = 3

hence total = 9 + 171 + 3 = 183.

What is the OA stolyar?

If one writes a list of integers from 1 to 1000, then how

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