I need help with a math queation

For one history test, keith had to answer 40 questions. of these 40 questions, keith answered 28 of them correctly. what percent did keith get on his history test? round your answer to the nearest tenth if necessary

Ian is in training for a national hot dog eating contest on the 4th of july. on his first day of training, he eats 4 hot dogs. each day, he plans to eat 110% of the number of hot dogs he ate the previous day. write an explicit formula that could be used to find the number of hot dogs ian will eat on any particular day.

An arithmetic series a consists of consecutive integers that are multiples of 4 what is the sum of the first 9 terms of this sequence if the first term is 0