If X:Y = 2:3, Y:Z = 4:5. Find X:Y:Z.

A. 2:3:5
B. 8:12:15
C. 2:8:5
D. 2:7:5
If A:B = m1:n1 ; B:C = m2:n2
Then, A:B:C = (m1*m2):(n1*m2):(n1*n2)
Therefore, X:Y:Z = (2*4):(3*4):(3*5)
= 8:12:15