If X:Y is 1:2 and Y:Z is 2:5 then X:Z is equal to	Pick:	A) 2 : 5	B) 3 : 5	C) 1 : 5	D) 4 : 5	E) 1 : 3

Rationale: "the two ratios given are having the same number 2 for y in both the ratios . hence - x : y = 1 : 2 y : z = 2 : 5 = > x : z = 1 : 5 answer c"
Answer: C