[Video] Q9: Nate walks 25 meters in 13.7 seconds. if he walks at this same rate, which of the following is closest to the distance he will walk in 4 minutes?

Explanation for Question 9 From the Math (Calc) Section on the Official Sat Practice Test 3

So now we're looking at number nine, which tells us about Nate, 2 who can walk 25 meters in 13.7 seconds. 3 And then it tells us if you walk at the same rate, 4 right? So he's walking at the same speed, which of the following is closest 5 to this since he would walk in four minutes. And so I think the 6 fastest way to go about this problem is to set up a proportion. 7 So you could call this a proportions problem and 8 I'll have what I know in the first fraction of my proportion and I'll 9 have what I'm trying to find in the second fraction of my proportion. 10 And so what I know is that Nate can walk 25 meters in 13.7 11 seconds. And then what I need to find is how far he walks, 12 right? So I'll put an X meters in my numerator here. 13 Cause I don't know that I'm going to find it, um, 14 over four minutes. 15 Right. But I'm not going to write four minutes in my denominator because I 16 see that I have a units of seconds right here. 17 So I want to be consistent with that. I need to convert the four 18 minutes into seconds and I do that by multiplying four by 60, 19 right? Cause there's 60 seconds per minutes. And that gives me 240 20 seconds. So now I have a fraction, 21 it's all set up. I'm trying to solve for a variable that's in the 22 fraction. And so what I'll do first is cross multiply. 23 I'll do 25 times 240, 24 right. Which will give me 6,000. And the 13.7 times X gives 25 me 13.7 X and then we'll solve for X. 26 I just need to divide both sides by 13.7, 27 these will cancel. And that leaves me with 437 28 being equal to X. And we see, 29 you know, that exact number is in the pro or in the answer choice, 30 but that's not an issue because the problem told us to find the closest 31 to what we got, which is closest to 450. 32 So our best answer then will be 450.