Explanation for Question 2 From the Math (No Calc) Section on the Official Sat Practice Test 6
Question two asks us a gardener buys two kinds of fertilizer fertilizer, 2 a contained 60% filler materials by weight and fertilizer B contains 3 40% filler materials by weight together. 4 The fertilizer is bought by the gardener contain a total of 240 pounds of 5 filler materials, which equation models, 6 this relationship where X is the number of pounds of fertilizer. 7 A and why is the number of pounds of fertilizer B? 8 So 240, as we can see all these answer choices. 9 That's what it's going to add up to for the total pounds 10 of filler materials. Now we know that it's going to be with X being 11 fertilizer, a plus Y, 12 but there's going to be some coefficient here. 13 And that's indicating what percentage of the pounds 14 of fertilizer a are going to be filler. 15 And what percentage of the pounds of fertilizer B are going to be filler 16 biggest? There's 240 pounds is just filler. 17 It's not the total weight. So for that reason, 18 we know that 60% of a is filler material. 19 So this is going to be our 60%. 20 And then we know that 40% of B is filling material. 21 So this is going to be our 40%. That means that we can cross 22 off. We can see that the 40 X in the 0.4 X doesn't look 23 like what we've got right here. Now we might be tempting to pick D 24 but actually the correct answer here is B because if you think of what 25 60% means, 60% is equal to six, 26 over 10, which is equal to 0.6. 27 And we want that percent times X, 28 not 60 times X, because then we'd end up with, 29 um, the wrong number, essentially for the total number of filler materials. 30 So we're going to have 0.6 X plus 0.4, 31 Y equals 240. 32 And that's exactly what's written in B.