Answer Choices
2
4
8
16
Explanation for Question 24 From the Math (Calc) Section on the Official Sat Practice Test 4
Not for question number 24, we're looking at a circle where a B is 2 the diameter. And then we're told that the length of the arc, 3 a D B this way is eight PI. 4 And so we need to know the length of the radius of the circle, 5 right? And so, as we think about the length of the arc, 6 right, we should see that this arc is one half, 7 which is our diameter, but we need to know what the diameter is in 8 order to find the radius, right? Because we'll take the diameter and then we'll 9 divide it by two. And so if we're talking about arc length, 10 we're going to want to have the equation for our claims in order to 11 do this problem. And the equation for our length is S or arc length 12 is equal to radius times beta. And the important thing to know is that 13 that feta is, uh, in ingredients, 14 right? 15 So if we're looking here, we're told that the S is eight PI, 16 we're going to solve for our radius here. And now, 17 if this is the, uh, the angle, 18 right, and we're told the abs the diameter, then that means that this is 19 really half of the circle, right? 180 degrees. 20 And you might immediately know that 180 degrees is PI, 21 or you could convert it, right. 180 degrees times PI 22 over 180, that's the conversion for converting things from PI into degrees 23 or, or the other way around. And these want to use cancel that simply 24 gives us pie, right? So if we're going to solve for our, 25 we need to divide both sides by PI. These PIs will cancel. 26 And we're told that our radius is eight, giving us answer choices.