AP EAMCET202420 May 2024Evening ShiftMathematicsPermutation and CombinationActual
The number of numbers lying between 1000 and 10000 such that every number contains the digits 3 and 7 only once without repetition is
Options
- A1140
- B918
- C720
- D810
Correct answer
C. 720
Step-by-step solution
No. of ways 0 = ^3 C ₂ 2 8=48 Total no. of ways aligned & = ^4 C₂ 2 8 8=64 12=768 & Required number =768-48=720 aligned