percentage word problems

Example 1

. Students made 25 red pennants and 30 yellow ones. They made ____more yellow pennants than red ones and the yellow pennants were________% more than the red ones.

Example 2

Tom planned to make 20 spare parts but actually made 25 spare parts. what is the percentage of increase?

 

Example 3

Tom planned to make 25 spare parts but actually made 20. what is the percentage of decrease?