Question

State which of the following statements are true and which are false. Justify your answer. 

(i) 37 ∉ {x | x has exactly two positive factors} 

(ii) 28 ∈ {y | the sum of the all positive factors of y is 2y} 

(iii) 7,747 ∈ {t | t is a multiple of 37}

Answer 1

(i) False 

Since, 37 has exactly two positive factors, 1 and 37, 37 belongs to the set. 

(ii) True 

Since, the sum of positive factors of 28 = 1 + 2 + 4 + 7 + 14 + 28 = 56 = 2(28) 

(iii) False 

7,747 is not a multiple of 37