Question
5 boys and 3 girls are to be seated on chairs arranged in a
row. If the arrangement is made at random, find the probability that no two girls will be seated next to one another.Solution
8 people can be seated on 8 chairs in 8! ways.
No two girls will be seated next to one another, so the arrangement would be like:
__ B __ B __ B __ B __ B __
5 boys can be seated at 5 places in 5! Ways. After this, 3 girls can be seated in the remaining 6 places in 6 P 3  ways.
Favorable outcomes= 5! XÂ 6 P 3 .
Probability = (5! x 6!)/(3! x 8!) = 5/14
60, 100, 160, 240, ?, 460
64, 32, ? , 48, 96, 240
What will come in place of the question mark (?) in the following series?
16, ?, 480, 1920, 5760, 115209 25 ? 121 221 337
...What will come in place of the question mark (?) in the following series?
17, 21, 30, 46, ?, 107
What will come in place of (?) Question mark in the given number series.
10, 15, 30, 75, 225, 787.5, ?
3, 5, 12, 38, 154, ?
4, 7, 12, 21, 36, ?
142, 148, 160, 178, ?, 232
5   3   4   7.5   17    ?    138
