Explanation for Question 18 From the Math (Calc) Section on the 2019 October Sat
Now number 18 is asking us, which of the following is closest to the 2 difference. So, first thing we need to know is we're finding a difference between 3 the percentage of adults, age 15, 4 18 to 50, who responded warm. So first let's find that box on here. 5 We want adults 18 to 50. 6 What we can notice is that we don't have that particular age range on 7 here. We have 18 to 35 and 36 to 50, 8 but if we put those together, right, if we look at the very low 9 and the very high, these two sets together are actually the 18 to 50 10 and we wanted the ones that responded warm. 11 So that's going to be those two boxes right there, 12 because those are the two age ranges that when we combine that, 13 it gives us the 18 to 50. Now the second number or percentage 14 probability that we wanted was age 51 or greater who responded 15 warm. 16 Right? And so that I'll highlight here in purple, 17 here's 51 to 65 and here's greater than 65. 18 And both of those combined gives us the whole 51 or greater, 19 greater. And so here are the ones that responded warm here. 20 And so now we just need to take these numbers and we need to 21 find the percentage. So let's start with the orange, 22 right? We're going to write a fraction. 23 And for our bottom, our numerator, we need our total. 24 And we'll find our total in this column. 25 I remember we added these two categories together. 26 So that means that we need to add the 5 0 8 and the four 10 27 to get our denominator for this fraction. 28 An...