Please help with math problem then write 5 sentences explaining the steps. (no links)

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

Solve this problem! extra ! 3025/5.5 = a/90.75

Awindow washer cleans 42 windows in 2 hours. at this rate, how many windows did he clean in 180 minutes.