Explanation for Question 18 From the Math (No Calc) Section on the 2017 April Sat
Question 18 says students in a science lab are working in groups to build 2 both a small and a large electrical circuit. 3 A large circuit uses four resistors and two capacitors, 4 and a small circuit uses three resistors and one capacitor, 5 there are a hundred resistors and 70 capacitors available and each group must 6 have enough resistors and the passengers to make one large and one small circuit. 7 What is the maximum number of groups that can work on this lab project? 8 Well, since we know that every group has to make one large and one 9 small circuit, we can combine those materials to find the minimum number of materials 10 that each group is going to need. And that's four plus three resistors, 11 which is seven resistors and two plus one capacitors, 12 which is three capacitors. However, 13 there's only a hundred resistors and 70 capacitors total. 14 Well with a hundred capacitors, 15 there could be 14 groups based on the amount each group would meet. 16 And with seven, eight, or sorry, resistors, 17 and with 70 capacitors, there could be 23 groups out 18 of those two numbers. 14 is smaller, 19 which tells us that 14 is the maximum number of groups that can work 20 on this project. And that's the correct answer.