Saved Bookmarks
| 1. |
How many 4 digit no arevthere with no digit repeated |
|
Answer» 9×8×7×6 8×8×7×6=2688 =10P4 - 9P3=[10!/(10-4)!] - [9!/(9-3)!] =(10×9×8×7)-(9×8×7)=9×8×7(10-1)=9×9×7×8=4536 It would be 9*9*8*7=4536 Total number 0,1,2,3,4,5,6,7,8,9=10digit 7,8,9,1=504 answer |
|