in the decimal system of numeration the number of 6-digit number in which the digit in any place is greater than the digit to the left of it is

total number : 9*8*7*6*5*4 as we want one of the arrangement of a single selection in which the digits are arranged in particular order. Hence, if we divide the total ways by 6!, we will get the desired result hence ans is (9.8.7.6.5.4)/6! Thanks and Regards, Pratik Tibrewal askiitians faculty BTech IITG