For this question, i'm having trouble taking the inverse. does the derivative need to be taken before the inverse is?

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?

You are at a restaurant and owe $56.20 for your meal. you want to leave an 18% tip. approximately how much is your tip?

Karen will divide her garden into equal parts. she will plant corn in 8/12 of the garden. what is the lowest number of parts she can divide her garden into?