The Total solution for NCERT class 6-12
The total number ofways to make an attempt to open the lock is = 10 × 10 × 10 = 1000
The number ofsuccessful attempts to open the lock = 1
The number ofunsuccessful attempts to open the lock = 1000 – 1 = 999
Hence, required numberof possible ways to make an unsuccessful attempt to open the lock is 999.