Explanation for Question 6 From the Math (Calc) Section on the Official Sat Practice Test 9
Question six refers to the same information as question five, 2 this graph, and this paragraph that asks us during 3 which of the following 10 minute intervals does the temperature of the coffee decrease 4 at the greatest average rate, instead of put this into other words we're looking 5 at, when does the temperature of the coffee decrease the fastest and in the 6 graph? That means when is the slope the greatest in the smallest amount of 7 time? When does the temperature drop the most? So we can just start 8 piecing together each point to see the slope between the different segments. 9 And hopefully you can kind of start to see as I'm drawing this out, 10 that the slope is clearly the greatest between zero and 10 minutes. 11 It decreases from about 195 degrees Fahrenheit to about 150 12 degrees Fahrenheit. And just 10 minutes. 13 Whereas later on, let's take these two points. 14 As an example, in this 10 minute span, 15 it decreases just a couple degrees. 16 So the temperature of the coffee decreases at the greatest average rate between zero 17 and 10 minutes, answer choice.