amc8試題及答案

1、Copyright © 2016 Art of Problem SolvingHow many square yards of carpet are required to cover a rectangular floor that is feet long and feetwide? (There are 3 feet in a yard.)First, we multiply to get that you need

2、square feet of carpet you need to cover. Since thereare square feet in a square yard, you divide by to get square yards, so our answer is .Since there are feet in a yard, we divide by to get , and by to get . To fi

3、nd the area ofthe carpet, we then multiply these two values together to get .2015 AMC 8 (Problems ? Answer Key ? Resources(http://www.artofproblemsolving.com/Forum/resources.php?c=182&cid=42&year=2015))Preceded

4、by First ProblemFollowed by Problem 21 ? 2 ? 3 ? 4 ? 5 ? 6 ? 7 ? 8 ? 9 ? 10 ? 11 ? 12 ? 13 ? 14 ? 15 ? 16 ? 17 ? 18 ?19 ? 20 ? 21 ? 22 ? 23 ? 24 ? 25All AJHSME/AMC 8 Problems and SolutionsThe problems on this page are co

5、pyrighted by the Mathematical Association of America (http://www.maa.org)'sAmerican Mathematics Competitions (http://amc.maa.org). Placement:Easy GeometryRetrieved from “http://artofproblemsolving.com/wiki/index.php?

6、title=2015_AMC_8_Problems/Problem_1&oldid=80323“2015 AMC 8 Problems/Problem 1SolutionSolution 2See AlsoThe octagon has been divided up into identical triangles (and thus they each have equal area). Since theshaded re

7、gion occupies out of the total triangles, the answer is .For starters what I find helpful is to divide the whole octagon up into triangles as shown here:Now it is just a matter of counting the larger triangles remember

8、 that and are notfull triangles and are only half for these purposes. We count it up and we get a total of of the shapeshaded. We then simplify it to get our answer of .2015 AMC 8 (Problems ? Answer Key ? Resources(http

9、://www.artofproblemsolving.com/Forum/resources.php?c=182&cid=42&year=2015))Preceded by Problem 1Followed by Problem 31 ? 2 ? 3 ? 4 ? 5 ? 6 ? 7 ? 8 ? 9 ? 10 ? 11 ? 12 ? 13 ? 14 ? 15 ? 16 ? 17 ? 18 ?19 ? 20 ? 21 ?