Which number stays the same when adding or subtracting fractions with unlike denominators?

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.

New york is the 27th largest state in the united states.what percent of the 50 states in the us are larger than new york

Ashley recently opened a store that sells only natural ingredients. she wants to advertise her products by distributing bags of samples in her neighborhood. it takes one person 22 minutes to prepare one bag. how many hours will it take to prepare 900900 bags of samples if ashley and 55 of her friends do the work?