if a number is choosen between 100 and 999 includeing these
numberrs what is the provbabilty that the number selected
does not contain a 7 is
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Answer Posted / seiko
no 0f 7's in 100 to 200 is
107,117,127,137,147,157,167,170,171,172,173,174,175,176,177,
178,179,187,197.
so total of 19 numbers between 100 and 199
repeat that for 200-299, 300-399,...,600-699, 800-899, 900-
999, we have 19*8 = 152 occurences
for 700-799, all 100 of them contain a 7
so total numbers contain a 7 is 152 + 100 = 252
total numbers between 100 and 999 is 900
probability = (900-252)/900 = 0.72
| Is This Answer Correct ? | 51 Yes | 8 No |
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