Let `X={a_1, a_2, ,a_6}a n dY={b_1, b_2,b_3}dot` The number of functions `f` from `xtoy` such that it is onto and there are exactly three elements `xinX` such that `f(x)=b_1` is 75 (b) 90 (c) 100 (d) 120

Let A = {x_1, x_2, x_3, ,x_7},B={y_1, y_2, y_3} The total number of functions f: A->B that are onto and there are exactly three element x in A such that f(x)=y_2 is equal to a. 490 b. 510 c. 630 d. none of these

Let A={x_(1),x_(2),x_(3)....,x_(7)},B={y_(1)y_(2)y_(3)} . The total number of functions f:AtoB that are onto and ther are exactly three elements x in A such that f(x)=y_(2) , is equal to

Let 'A={1,2,3,.....n}' and 'B={a,b,c}' , the number of functions from A to B that are onto is

If f:A rarr B,A={1,2,3,4},B={1,2,3} and f(i)!=i then the number of onto functions from A to B is

If n(B)=2 and the number of functions from A and B which are onto is 30, then number of elements in A is (A) 4 (B) 5 (C) 6 (D) none of these

The total number of onto functions from the set A={a,b,c,d,e,f} to the set B={1,2,3} is lambda then (lambda)/(100) is

Let A = {1, 2, 3, 4} and B = {a, b}. A function f : A to B is selected randomly. Probability that function is an onto function is