Question

Which of the following is an equal set?

• A. A = Set of prime numbers less than 6 B = set of prime factors of 30
• B. A = {x: x - 5 = 0} B = {x: x is a integral root of the equation -2x-15=0 }
• C. A = {x: x is even integer and x 10} B = {2, 4, 6, 8, 10}
• D. A = {x: x is a letter in the word FELLOW} B = {y: y is a letter in the word WOLF}

Answer 1

The correct option is A

A = Set of prime numbers less than 6

B = set of prime factors of 30

(a) A = {2, 3, 5}

B = {2, 3, 5} out of factors of 30 = {1, 2, 3, 5, 6, 15, 30}

(b) A = {5}

B = {-3, 5} roots of $x^2$-2x-15=0 which are -3, 5.

(c) A = {$-\infty$,- - - - -, -4, -2, 0, 2, 4, 6, 8, 10}

B = {2, 4, 6, 8, 10}

So, A$\ne$B

(d) A = {E, F, O, L, W}

B = {F, O, L, W}

So, A $\ne$ B

So, A & B in option (a) are equal sets.