Q24 of 68 Page 341

How many different products can be obtained by multiplying two or more of the numbers 3, 5, 7, 11 without repetition?

The given no. is 3,5,7,11.


The no. of different products when two or more is taking= the no. of ways of taking the product of two no.+ the no. of ways of taking the product of three no. + the no. of ways of taking the product of four no.


= 4C2 + 4C3 + 4C4


Applying nCr =


= 6+4+1


=11


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