1) a farm has chickens and cows. you ask the farmer how many chickens he has, and how many cows he has. the farmer tells you he has 28 healthy animals, and they have a total of 64 legs. how many of his animals are cows?
2) andrew has a collection of soda bottles. some of them are 12-ounce bottles, and others are 16-ounce bottles. if the collection contains 20 bottles which hold a combined 300 ounces, how many of the soda bottles are 12-ounce bottles?
need two variables and two equations for each. it also needs to be solved.

Find the number of positive three-digit even integers whose digits are among 9, 8, 7,5, 3, and 1.

Student price tickets to a movie are $1 and non student tickets are $2. 350 tickets are sold and the total amount made is $450. how many non student tickets were sold ? a) 100 b) 150 c) 200 d)250

Afriend of mine is giving a dinner party. his current wine supply includes 10 bottles of zinfandel, 8 of merlot, and 11 of cabernet (he only drinks red wine), all from different wineries. (a) if he wants to serve 3 bottles of zinfandel and serving order is important, how many ways are there to do this? ways (b) if 6 bottles of wine are to be randomly selected from the 29 for serving, how many ways are there to do this? ways (c) if 6 bottles are randomly selected, how many ways are there to obtain two bottles of each variety? ways (d) if 6 bottles are randomly selected, what is the probability that this results in two bottles of each variety being chosen? (round your answer to three decimal places.) (e) if 6 bottles are randomly selected, what is the probability that all of them are the same variety? (round your answer to three decimal places.)