Math miscellaneousEasy
Question
The value of 50C4 + 
56-rC3 is
56-rC3 is Options
A.55C4
B.55C3
C.56C3
D.56C6
Solution
56C4 + 
56-rC3
⇒ 50C4 + [55C3 + 54C3 + 53C3 + 52C3 + 51C3 + 50C3 ]
= (50C4 + 50C3) + 51C3 + 52C3 + 53C3 + 54C3 + 55C3
(51C4 + 51C3) + 52C3 + 53C3 + 54C3 + 55C3
⇒ 55C4 + 55C3 = 56C4.
56-rC3 ⇒ 50C4 + [55C3 + 54C3 + 53C3 + 52C3 + 51C3 + 50C3 ]
= (50C4 + 50C3) + 51C3 + 52C3 + 53C3 + 54C3 + 55C3
(51C4 + 51C3) + 52C3 + 53C3 + 54C3 + 55C3
⇒ 55C4 + 55C3 = 56C4.
Create a free account to view solution
View Solution FreeMore Math miscellaneous Questions
If f(y) = ey, g(y) = y; y > and F(t) =f(t - y)g (y) dy, then...If a, b, c are distinct +ve real numbers and a2 + b2 + c2 = 1 then ab + bc + ca is...The mean of the numbers a, b, 8, 5, 10 is 6 and the variance is 6.80. Then which one of the following gives possible val...If x = y (log y - log x + 1), then the solution of the equation is...The number of ways in which 6 men and 5 women can dine at a round table if no two women are to sit together is given by...