http://sat.collegeboard.org/practice/sat-question-of-the-day?src=R&questionId=20130125 (This link takes you to today’s question. If you use my archive, you will see the question related to my SAT explanation for that date.)
The answer is D. This SAT question is a “mutually exclusive” probability question and you can also see this issue on the ACT. If you pick a red marble, you can’t pick a green one. By subtraction you know that 1/3 of the marbles are green and, therefore, 1/3 is 36 marbles. That means that twice as many (2/3 (red) = 2(1/3 (green)). So, 2 times 36 = 72 red one.)
This not an uncommon question type so you need to learn what “mutually exclusive” means: if one event occurs, then it excludes another even from occurring. If you get a heads when you flip a coin, you can’t get a tails. The individual probabilities of related mutually exclusive events has to add up to 1. In the sample question, 2/3 plus 1/3 equals 1. You can learn more about this issue on my website, on my SAT and ACT DVD set, or in my class.
I wonder what the ACT folks are up to this morning.
http://www.act.org/qotd/ (The ACT staff does not put a date on their questions so if you click on an archived blog, you’ll get today’s question and the old explanation. Sorry. The SAT staff has dated their questions; so, the archive is helpful. The ACT folks simply don’t do that.)
The answer is B. You know that like topic sentences introduce paragraphs, concluding sentences summarize paragraphs and/or provide a transition to the next paragraph. In this case, we need a summary. Even if you don’t know the word “chaos,” you know that C and D make no sense. But the ACT writers defined chaos in the paragraph so you would know what it means! That made finding the right answer easier. Don’t count on the ACT staff making it this easy all the time.
Classes start in Dr. Phillips, Lake Nona, and Celebration next week. Register now and save a seat.
Osceola students–if you’ve done the practice test and have a question about any of the items, let me know and I’ll help you. The test is only a few days away.
If you are taking the January SAT and/or February ACT, time is running short. I recommend you watch my online Tips and Tricks videos to help you prepare. In addition to the free ones on the home page, it only costs $3 to watch an hour of my best test-taking techniques for taking the SAT and ACT tests.