Darrin put the numbers 7.25, 7.52, and 5.72 and 5.27 in order from greatest to least. is his work correct? explain

If the order of the numbers in the question are the order Darrin put theem in then no, his work is not correct. this is because 7.25 is not greater than 7.52. the real order should be 7.52,7.25, 5.72, 5.27

His work was incorrect, the number has the  most value is the greatest number
Because 7 > 5, then 7.25 and 7.52 will be 1st and 2nd numbers and 5.72 and 5.27 will be 3rd and 4th numbers. 
Let's compare 7.25 and 7.52
Because 2 < 5 (the tenth digit) so 7.52 is 1st number and 7.25 is the 2nd number
Now, compare 5.72 and 5.27, again, 7 > 2 (the tenth digit) so 5.72 is 3rd number and 5.27 the 4th number.
Totally, the order from greatest to least is 7.52 , 7.25 , 5.72 , 5.27