Q5 of 118 Page 17

Write the value of .

We know,


nCr + nCr-1 = n+1Cr


Now, we have,


56-rC3 + 50C4


= 55C3 + 54C3 + 53C3 + 52C3 + 51C3 + 50C3 + 50C4


= 55C3 + 54C3 + 53C3 + 52C3 + 51C3 + 51C4


= 55C3 + 54C3 + 53C3 + 52C3 + 52C4


= 55C3 + 54C3 + 53C3 + 53C4


= 55C3 + 54C3 + 54C4


= 55C3 + 55C4


= 56C4


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