Explanation for Question 23 From the Math (Calc) Section on the 2018 May Sat
Question 23 says in 1789, 2 Benjamin Franklin gave an amount of money to Boston, 3 Massachusetts. The money was to be invested for a hundred years in a trust 4 fund. If the value of the trust fund doubled every 10 years, 5 which of the following graphs, best models and the value of the trust plan 6 over time for the 100 years. 7 So what we know here is we know that the money is increasing, 8 that it's always increasing, which tells us that B is wrong because at some 9 points it becomes, uh, 10 it becomes stagnant. And we also know that it's not increasing at a 11 constant rate. It's increasing exponentially. 12 So since it's not increasing at a constant rate, 13 we can eliminate a and since we know it's increasing exponentially, 14 we know that sees the correct answer. The reason that D is wrong is 15 because it's constantly increasing it, 16 doesn't increase and then stay constant for a while and then increase. 17 It's a constant increase. So that tells us that C is correct and D 18 is incorrect.