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In how many ways 4 boys and 3 girls can be seated in a row so that they are alternate.

A. 144

B. 288

C. 12

D. 256

Answer: Option A

Solution(By Examveda Team)

Let the Arrangement be,
B G B G B G B
4 boys can be seated in 4! Ways
Girl can be seated in 3! Ways
Required number of ways,
= 4! × 3!
= 144

This Question Belongs to Arithmetic Ability >> Permutation And Combination

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Comments ( 3 )

  1. Avni
    Avni :
    2 months ago

    when seating 4 boys and 3 girls alternatively in a row, consider them as distinct entities. you have 7 individuals to arrange.
    the possible arrangements for B (boys) and G (girls) are as follows:

    1. BGBGBGB
    2. GBGBGBB
    3. GBGBBGB
    there are 2 possible arrangement for the sequence of B and G. within each gender, the individuals can be arranged among themselves.

    so, the total number of ways is (2times 4!time 3!=2times 24 times 6 = 288).

    therefore, there are 288 ways to seat 4 boys and 3 girls alternatively in a row.

  2. Mani Kumar
    Mani Kumar :
    7 years ago

    Dear Nagamani,
    ! means "Factorial"
    Ex: 1!=1
    2!=1x2=2
    3!=1x2x3=6
    4!=1x2x3x4=24
    ......................
    ......................
    n!=1x2x3x4x5x6x........xn

    Thanks..

  3. Nagamani
    Nagamani :
    8 years ago

    i dont understand these solutions what 4!3!means what '!' symbolises

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