Functions : work out the input when the output from function c is 54

Ill mark the brainliest if you me with the these three questions 7,8,9

Kira looked through online census information to determine the overage number of people living in the homes in her city what is true about kira's data collection?

Jim had 3,067.48 in his checking account he wrote a check to pay for two airplane tickets. his account now has 1,845.24.