Question

If A = {3, 5, 7, a} and B = {4, 6, 25, 27, 54, 100}, a E A b E B find the set of ordered pairs such that "a" is a factor of "b" and a < b

Answer 1

A = {3,5,7,a}, B = {4,6,25,27,54,100}

given, a \(\in\) A, b \(\in\) B and a is factor of b such that a < b.

Possible pair If a = 2 then b = 4, 6, 54, 100

If a = 4 then b = 100

If a = 6 then b = 54

If a = 25 then b = 100

If a = 27 then b = 54

If a = 9 then b = 27, 54

If a = 10 then b = 100

If a = 18 then b = 54

If a = 20 then b = 100

If a = 50 then b = 100

Therefore, the set of ordered pair (a,b) are {(2,4), (2,6),(2,54),(2,100),(4,100),(6,54),(9,27),(9,54),(10,100),(18,54),(20,100),(25,100),(27,54),(50,100),(100,100)}