HOW MANY INTEGERS FROM 1 TO 100 DO NOT INCLUDE THE DIGIT 1

Toán ĐỀ THI TOÁN QUỐC TẾ PMWC VÒNG CÁ NHÂN

3. How many integers from 1 to 100 do not include the digit 1? 1 of his money to his son, 1 of his money to his daughter and the