Answer Choices
2
4
5
6
Explanation for Question 18 From the Math (Calc) Section on the Official Sat Practice Test 4
Not for number 18. We're told that Jim has identical drinking glasses and the 2 shape of a right circular cylinder and a, 3 with a diameter of three inches. And then we're told that he pours the 4 milk from a gallon jug into each glass until full. 5 And the height of the milk in each glass is six inches. 6 Right? So we need to know that we've got a Sprite, 7 circular cylinder. It appears that we've got a diameter here of three 8 inches and then the height, it appears is six inches. 9 Once they're filled all the way full. Right. And so we need to know 10 what is the largest number of, uh, milk glasses that he can pour from 11 a one gallon jug. So essentially what we need to know right is first, 12 what is the volume of the, 13 uh, of the milk glass? And then we need to convert that into, 14 um, from a gallon, right? 15 So the volume of a cylinder is PI R squared times the height, 16 right? And so we have PI our radius is half of our diameter. 17 So in this case, it's 1.5 squared. 18 Um, and then our height is the six inches, 19 right? So we've got PI times 1.5 squared. 20 We're just going to plug that in our calculator times six, 21 which gives us 42. So our volume is 42.4, 22 one about inches cubed per milk glass. 23 Right. But one gallon is the same as 231. 24 So if I can have 231 inches cubed and a Gatlin, 25 how many times can I put 42.4, 26 one into that? And so we can just divide those, 27 right? We need to do 2 31 divided by the 42, 28 um, which is 5.44. 29 So now it's our question. Okay. It's between five it's between six. 30 So can I fill up five classes or six classes and they need to 31 know the largest number of full glasses, 32 right? So I can fill up five full glasses and then I'll have one 33 glass it's about halfway full, right? 34 So I can't fill up that six glass. I can only fill up five 35 glasses, making our best answer C.