Current location - Training Enrollment Network - Mathematics courses - There are 100 athletes participating in the marathon. Give them the number plates of 1~ 100 respectively. How many athletes have the number 7 on their number plates?
There are 100 athletes participating in the marathon. Give them the number plates of 1~ 100 respectively. How many athletes have the number 7 on their number plates?
The numbers with 7 in 1- 100 are respectively

1 odd 7

1 digit,1digit, 7 digits, 77 digits.

17.27.37.47.57.67.87.97 There are 7 in the octet.

70.71.72.73.74.75.76.78.79 There are 7 units.

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