in unit's place, the 3's are:

3, 13, 23 ... 73

103, 113, 123 ... 173

...

703, 713, .... 773

=> total number of 3's in unit's place is 8*8 = 64

in 10's place (that's 8 in decimal), the 3's are:

30, 31, 32... 37

130, 131, ... 137

...

730, 731, .... 737

=> total number of 3's in 10's place is 8*8 = 64

in 100's place (that's 64 in decimal), the 3's are:

300, 301, ... 307

310, 311 ... 317

...

370, 371 .... 377

=> total number of 3's in 100's place is 8*8 = 64

thus, the total number of 3's in total is 64 + 64 + 64 = 192

## Bookmarks