Explanation for Question 17 From the Math (No Calc) Section on the 2017 May Sat
For 17, we're going to first read the paragraph and then determine what we 2 need to do. So the question reads, 3 Isabella sells only rings and necklaces on her website ring sells 4 for 50 each and necklaces sell for 30 each. 5 If Isabella sold 25 pieces of jewelry and her sales totaled $1,050, 6 how many necklaces did Isabella set? 7 So, so here we have two sets of information. 8 We have that she sold rings and necklaces, 9 and then she sold a total of 25 of those. 10 And then we have the prices for each and we know how much money 11 she sold or got in total. 12 So we want to create a system of equations to find out how many 13 necklaces Isabella's assault. 14 Our first equation should be based on the number of pieces of jewelry. 15 So it should be equal to 25. And our second equation should be equal 16 to the money that she made her sales. 17 So 10, 1,050. 18 So these two equations will be, 19 we have to think about what adds up to 25 and what ends up 20 to 25 is the rings. Plus the necklaces, 21 the amount of rings, plus the amount of necklaces that equals 25. 22 Now what adds up to the 1,050 is the money 23 that she makes from the rings and the money that she makes from the 24 necklaces or how much she charged for a ring, 25 which is 50. And how much you charge for a necklace, 26 which is 30, that added together equals 10 50. 27 And now we can go through and solve by substitution to find out, 28 um, how many necklaces she sold. 29 Our first step will be to solve one equat...