Find x:y:z if x:y = 2:3 and y:z =2:3

Please explain answer.

You are given x:y and y:z, so the "link" is y

Try to get the same value of y in each proportion ..
x:y = 2:3 = 4:6
y:z = 2:3 = 6:9

so x:y:z = ......