Question

29. P, Q, R and S are 5-digit numbers, each having the digit 9 only once and in
the place shown. None of the other digits are known.
(P) 9
(Q) 9
(R)
(S)
9
9
tomonte is
PRECT about P R and S?​

Answer 1

Answer:

Correct option is

B

9×

9

P

4

To form a number with 5 distinct digits can be given by

For the first digit, there are 9 choices as 0 can't be used at first place

Now, we can choose any of the remaining 9 numbers at the second place.

For the third place, we can use any of the remaining 8 digits which are not used at first two places.

We can use remaining 7 digits at the fourth place and for the last digit we can use remaining 6 digits.

So, the total number of numbers having 5 digits is 9×9×8×7×6=9×

9

P

4

.