A letter lock contains 3 rings and each ring contains 5 letters. Deter

1.	A letter lock contains 3 rings and each ring contains 5 letters. Determine the maximum number of false trails that can be made before the lock is opened.
Answer» A letter lock has 3 rings, each ring containing 5 different letters. ∴ A letter from each ring can be selected in 5 ways. ∴ By using the fundamental principle of multiplication, a total number of trials that can be made = 5 × 5 × 5 = 125. Out of these 124 wrong attempts are made and in the 125th attempt, the lock gets opened. ∴ A maximum number of false trials = 124

A letter lock contains 3 rings and each ring contains 5 letters. Determine the maximum number of false trails that can be made before the lock is opened.

Answer»

A letter lock has 3 rings, each ring containing 5 different letters.

∴ A letter from each ring can be selected in 5 ways.

∴ By using the fundamental principle of multiplication,

a total number of trials that can be made = 5 × 5 × 5 = 125.

Out of these 124 wrong attempts are made and in the 125th attempt, the lock gets opened.

∴ A maximum number of false trials = 124