The Least Common Multiple of two prime numbers x and y, (xy) is 145. Then what is the value of (10x - y)?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 21.
(x) and (y) are prime numbers, we begin by finding the prime factorization of 145:
⇒ 145 ÷ 5 = 29
⇒ 145 = 5 × 29
(x = 5) and (y = 29), we can substitute these values into the expression (10x - y):
⇒ 10x - y = 10(5) - 29 = 50 - 29 = 21