Question

△X′Y′Z′ is the image of △XYZ under a dilation through point C. XZ=4 and X′Z′=5 .

Answer 1

Divide the two lengths: 
(X'Z')/(XZ) = 5/4 = 1.25

The final answer is choice D) 1.25

This means that the larger figure is 25% bigger in size (comparing corresponding segments).

Answer 2

The answer is 1.25.