If m denotes the number of 5 digit numbers if each successive digits are in their descending order of magnitude and n is the corresponding figure, when the digits are in their ascending order of magnitude then (m – n) has the value
Know your College Admission Chances Based on your Rank/Percentile, Category and Home State.
Get your JEE Main Personalised Report with Top Predicted Colleges in JoSA
m – n = 10C5 – 9C5 = 252 – 125 = 126 = 9C5 or 9C4
Alternatively: 9C5 + 9C4 – 9C5 = 9C4 = 9C5