What is a two word phrase used to show division in a word problem?

Apackage of bacon holds 15 strips of bacon. the pancake house uses 17 packages of bacon in the morning and 21 packages in the afternoon. how many more strips were used in the afternoon than the morning?

Alicia puts $400 in a bank account. each year the account earns 5% simple interest. how much money will be in her bank account in six months?

I’m still confused on how to work the percentages