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### Building Puzzle

Building Puzzle - 16 November

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

1. from 1 to 99 consider all numbers as two digit numbers
00
01
02
.
.
.
99

so total no.of digits=2*100=200
each digit (0,1,....9) appears equal no.of times so 9 appears=200/10=20 times from 1 to 100

2. 20 9's r there.

3. 20, 09-89 = 9, 90-99 = 11

4. There are another 20 "9"s upside down!!!!!!

5. 20 bcz 9,19,29,39,49,59,69,79,89,90,91 92 93 94 95 96 97 98 99.hre there r 20 9's present hence the answer is 20

1. that amounts to 19 dumb ass

2. You have to count 99 twice dumb ass.

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7. there are 20- 9's

8. only single "9"

9. 1. 09
2. 19
3. 29
4. 39
5. 49
6. 59
7. 69
8. 79
9. 89
10. 90
11+12. 99
the 9. 89 would technically 13

10. 20 9s are used for 1 - 100 street numbers

11. 40.
There are 20 9's and 20 6's which is nothing but '9' reversed.

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13. There's 11 because
9
19
29
39
49
59
69
79
89
That's 9 and then for 99 there are 2 so it's 11