Hey there!
Let's take a look at their decimal places.
For 0.4, the four is in the tenths place, therefore it's 4/10
For 0.25, the number ends in the hundredths place, therefore it's 25/100
To compare them, I can make the 4/10 out of 100 and we'll see which has the larger denominator.
To do this, we multiply 4/10 by 10/10 to get 40/100.
40/100 is greater than 25/100, so Luke lives closer to the skating rink.
Hope this helps@