SAT ? of the Day 10/8/08

Yesterday's Answer
Correct Answer: A

Here's Why:
In order to find the value of x, you should first determine the measure of the angle that is located at point O in the right triangle. To determine this angle, you must calculate what fraction of the circle’s area is unshaded. The radius r of the circle is 5 and its area isr2, or 25. The area of the shaded region is 20, so the area of the unshaded region must be 5. Therefore, the fraction of the circle’s area that is unshaded is
, or . A circle contains a total of 360 degrees of arc, which means that of 360 degrees, or 72 degrees, is the measure of the angle at point O in the unshaded region. Since you now know that two of the three angles in the triangle measure 72 degrees and 90 degrees and that the sum of the measures of the three angles is always 180 degrees, the third angle must measure 18 degrees. Therefore, x = 18.

Difficulty: Hard
Question Type: Standard Multiple Choice
(Mathematics)
Today's ?

Choose the word or set of words that, when inserted in the sentence, best fits the meaning of the sentence as a whole.

The test of truth is not ------- , for we have often felt firmly convinced of many things that were not so.

1. implication


2. certitude


3. originality


4. impartiality


5. moderation