Step-by-step explanation: There's a special jingle I like to use that goes like this: "Thirty days hath September, April, June, and November! All the rest have 31, except for February, with 28 days clear and 29 in each leap year." February is the second month and has 28 days non-leap year and September is the ninth with 30 which we got from the jingle. Add them up and boom, 58.
