Explanation for Question 4 From the Math (Calc) Section on the 2017 May Sat
Question four says know, 2 sold boxes of cookies and bags of candy. 3 The ratio of the number of boxes of cookies. 4 She sold to the number of bags of candy. 5 She sold was two to one. 6 If unit sold eight box of cookies, 7 how many bags of candy did she sell? 8 So the important part here is that they tell us that the ratio, 9 um, of boxes of cookies to box of candy was two to one. 10 We can write that like that or like this, 11 or even like this, these all mean the same thing, 12 essentially. It just means that she sold twice as many boxes of cookies. 13 As she did bags of candies, we want find out how many, 14 um, bags of candy she sold. 15 If she sold eight bags of cookies. So we can set up a proportion 16 comparing the two to one, 17 two, how many she actually sold. 18 So if we have two to one, if that's what our ratio needs to 19 be, a proportion would be eight over 20 X, two over one equals eight over X, 21 because on the numerators, 22 we have the boxes of cookies and the denominator. 23 We have the bags of candy again to solve proportions. 24 All we do is we cross multiply. 25 So let's move this out of the way. So we have a little more 26 space and now we cross multiply. 27 We got two X equals one times eight is just eight to 28 solve for X. All we do is we divide by two in both sides 29 and we got X equals four. 30 She sold four bags of candy, 31 a.