Question bank/JEE Main/Mathematics
JEE MainMathematicsModeratePermutations and Combinations
Number of ways in which AAA BBB can be placed in the squares of
the figure as shown, so that no row remains empty, is
Show answer and solution
We have to arrange A, A, A, B, B, B in the squares of the fig.
So that no row remains empty.
First of all the total no. of ways of filling 9 squares with 6 things
[IMAGE] Now counting the ways in which any of rows remain empty.
For this we have the situation when the given ' 6
occupy exactly two rows completely and this will happen in
[IMAGE] So required number of ways in which no rows remain empty = 1680 - 60
=
So that no row remains empty.
First of all the total no. of ways of filling 9 squares with 6 things
[IMAGE] Now counting the ways in which any of rows remain empty.
For this we have the situation when the given ' 6
occupy exactly two rows completely and this will happen in
[IMAGE] So required number of ways in which no rows remain empty = 1680 - 60
=
Source: Grass-G / M-10 Mathematics Paper-1 30 Oct.docx
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