"How many times more did Carol eat compared to Dima?" is quite different from the previous question, in which you asked "how much more did Carol eat than Dima?" I think they ate 10/25 and 9 /25 of the cake, respectively.
10/25 is greater than 9/25, obviously. We need to calculate "how many times greater is 10/25 than 9/25? So we divide 9/25 INTO 10/25. This comes out to 10/9, or 1.11 times as much. Carol eats 11% more cake than Dima. Hope she doesn't gain too much extra weight. ;)
