there were 5832 entries in the contest if there had been 168 more. How many winning entries would there have been

This can be viewed several different ways. If there were 168 more entries there are 5832-168 entries now. There is no information regarding the number of percentage of winning entries so the total cannot be determined without additional information.

i think for that you need to give the number of winning entries that could be when there were 5832 entries in the contest!

becoz after having that only we can get the number of added ones