Explanation for Question 9 From the Math (Calc) Section on the 2019 May Sat
So question nine asks the graph above shows the temperature in a room during 2 the day when the thermostat malfunctioned, for which of the following two hour periods 3 was difference between the maximum and minimum temperatures greatest. 4 So to find the answer to this problem, 5 we're going to need to look at the two hour time periods in each 6 answer, find the maximum and minimum temperatures calculate 7 the difference based on that, and then compare the answer choices to see, 8 which has the greatest difference. 9 So let's start with option a. 10 So the time period is one to three. 11 The minimum temperature during that time is 50 and the maximum temperature 12 is about 55 ish. 13 So 55 minus 50 equals 14 five. So the difference for answer a is five. 15 Now let's compare that to answer B, 16 which is from three to 5:00 PM. 17 The lowest temperature is a little under 55. 18 So maybe about 53 ish. 19 You might have to estimate a little bit, oh, 20 I wrote that in the wrong spot. It's my bad. 21 So around 53 ish, 22 53 and the maximum is up here at 70. 23 So 70 minus 53 gives us 17. 24 That's much greater than five. The difference is much greater for B. 25 So we can eliminate, that's like an answer choice C from 26 five to seven. So the maximum and answer choice 27 C is about 85 and the minimum 28 so you can see right here is that 70. 29 So that is equal to 15 and we can eliminate answer choice 30 C because that's less than 17. 31 And then finally, let's look at seven to nine. 32 The maximum is around here. So at about 85 and 33 the minimum is right here at about 80, 85 34 minus 80 is equal to five and that's less than 17. 35 So that means that the answer is B because that time period three to 36 5:00 PM has the biggest difference between its maximum and 37 minimum minimum temperatures. So be it.