Question

how many 4 digit numbers can be formed using the digits 1,2,3,4,5,6,7, where repetition is allowed ​

Answer 1

Answer:

Step-by-step explanation:

N^2 is the formula when repetation is allowed

So 49 is the answer



Answer 2

Answer:

2401

Step-by-step explanation:

_ _ _ _

there are 4 digit

according to question

ones place can be filled by 7 digits

tens place can be filled by 7 digits

hundreds place can be filled by 7 digits

thousands place can be filled by 7 digits

so the answer is (7)⁴= 2401