Question

How many 4 digit numbers can be made using 1, 2, 3, 4, 5, 6 and 7 with none of the digits being repeated? ​

Answer 1

Answer:

480

Step-by-step explanation:

Place 4 in all the four places one by one and arrange the rest.

4 _ _ _ = 1*6*5*4 = 120

_ 4 _ _ = 6*1*5*4 = 120

_ _ 4 _ = 6*5*1*4 = 120

_ _ _ 4 = 6*5*4*1 = 120

Total = 120*4= 480.