If you are reading this in an email you received from me, do not click the link to sat.collegeboard.org below. Use the link to my website that is farther down on the email.
http://sat.collegeboard.org/practice/sat-question-of-the-day?questionId=20131218&oq=1 (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 key to all circle questions is the radius. Watch Video #7: Geometry and read my website for more information about this principle.
The answer is C. The radius of this circle is 4 which means the diameter is 8. So, both ends of a line of length 8 would touch the circumference of the circle. Any line that is shorter than the diameter would fit inside the circle. That eliminates D and E. Of the three remaining answers, the longest one is C, 7.99.
There is a characteristic of this question that is very rare on the test. I only remember two other geometry questions in the last 22 years that had extra information (and I watch for it). There’s extra information in this question and it is used to confuse you. The line that is 7 long doesn’t need to be provided for you to answer the question. However, you can use the information (but it isn’t necessary) to answer the question.
We’ve already eliminated D and E. Use the line of length 7 to eliminate Answers A and B. Look at the circle. If the left-hand end of the 7 line were to be moved clockwise (closer to being a diameter), it would have to get longer to reach the circumference which makes an answer of 6.99 completely stupid. Once the left-hand end of the line becomes a diameter, you know it has to be 8 and that’s too big to answer the question. However, if it doesn’t quite become a diameter, you’ve found the answer: 7.99.
Let’s see what the ACT folks have for us today.
ACT Question of the Day: Use your “back” button to return to my website after reading the ACT Question of the Day.
This is an easy question that simply requires you to remember how long the stake is: 1 meter. In the question, they give you the fact that the length of the shadow will be the same length as the stake. The only time that length appears in a table is Day 3 of Experiment 2. There’s your answer.
Do you know what the most important thing is to learn from this question? First, you’ll never predict the science knowledge that will be on the test; so don’t worry about reviewing science information as part of your test prep. Second, they’ll explain the science on the test which is all the more reason to not review science topics. Third, this is a science reasoning test. You need to apply scientific principles and the most important skill is analyzing and interpreting data. That is what you need to practice prior to the test. Get your hands on some actual ACT Science Tests and study the way the test writers present data and ask questions about the charts and graphs in those tests–the more the better. Work on your speed because that is the major challenge of the test. Let’s get to work! Only practice will raise your score.
Some of you are already on Christmas break; others are counting the days until it starts. What are you going to do to make it a productive one? And I don’t mean just about school and SAT/ACT stuff! What are you going to do to get closer to your family and friends? It is a wonderful opportunity to work on your relationships because you have time. I hope you’ll look back on January 2 and say, “It was time well spent.”
The SAT & ACT Wizard