Math miscellaneousEasy

Question

The number of five digit numbers that contains digit 7 exactly once is if digits may be repeated)

Options

A.(41) (93)
B.(37)(93)
C.(7) (94)
D.(41)(94)

Solution

- ∴ if 7 fill in
                                     first place
= 32 × 93 if 7 can be
                            fill in any last 4
94 + (32 × 93) = 41 × 93 places

Create a free account to view solution

View Solution Free
Topic: Math miscellaneous·Practice all Math miscellaneous questions

More Math miscellaneous Questions

Given , where . Then (λ + μ + v) is equal to -...The number of ways in which 6 men and 5 women can dine at a round table if no two women are to sit together is given by...f(x) = ; At x = 0 : f(x) is :-...Let a1, a2, a3, ... be terms of an A.P. If, p ≠ q, then equals...A and B are events such that P(A ∪ B) = 3 / 4, P(A ∩ B) = 1/ 4, P() = 2/3 then P( ∪ B) is...