Question

How many can 3 digits be formed using the digits from 1 to 5 if the digit 2 is never there in the number?

Answer 1

Answer:

 4∗4∗4=64 .

Step-by-step explanation:

.There are 5 digits from 1 to 5 but the digit 2 is not to be used while forming 3-digit numbers. So, there are 4 admissible digits viz 1,3,4 & 5. Now, assuming the repetitions of the digits, the hundreds place can be filled by any of the 4 digits in 4 ways. And for each such digit in hundreds place, the tens place can also be filled in by any of the 4 digits in 4 ways. And lastly, the unit place can also be similarly filled in 4 ways. Hence, total number of required 3-digited numbers will be  4∗4∗4=64 .