x, y, a, and b are four positive integers. D is the greatest common divisor of x and y. Is D > 20?
(1) x = 10a + 20b = 10 (a+2b)
No information on y is available. So we cannot determine GCD of x and y.
Statement 1 is not sufficient.
(2) y = 20a + 40b = 20 (a+2b)
No information on x is available. So we cannot determine GCD of x and y.
Statement 2 is not sufficient.
Statement 1 and 2 together
y = 2x.
Since, x = 10*(a +2b), which is common to both x and y, and a and b are positive integers(minimum value 1) so their sum will also be a positive integer (1+2*1 = 3)
therefore we see that GCD (D) of x and y is atleast 30 i.e., D is greater than 20.
Answer C
(1) x = 10a + 20b = 10 (a+2b)
No information on y is available. So we cannot determine GCD of x and y.
Statement 1 is not sufficient.
(2) y = 20a + 40b = 20 (a+2b)
No information on x is available. So we cannot determine GCD of x and y.
Statement 2 is not sufficient.
Statement 1 and 2 together
y = 2x.
Since, x = 10*(a +2b), which is common to both x and y, and a and b are positive integers(minimum value 1) so their sum will also be a positive integer (1+2*1 = 3)
therefore we see that GCD (D) of x and y is atleast 30 i.e., D is greater than 20.
Answer C
Statistics : Posted by sivakumarm786 • on 16 Feb 2023, 01:30 • Replies 2 • Views 96
