Explanation for Question 12 From the Math (Calc) Section on the 2019 May Sat
So question 12 asks Tanya earns 13, 2 $13 and 50 cents per hour at her part-time job. 3 When she works at Z hours, she earns 1350 Z dollars, 4 which of the following expressions gives the amount in dollars. 5 Tonya will earn if she works three Z hours. 6 So the original equation here is 1350 Z 7 and we're replacing Z with three Z, 8 right? So this becomes 13, 9 50 times three Z. 10 Um, and it doesn't matter which order we're multiplying in. 11 So it could also be three times 1350 Z, 12 which is how the test writers wrote, 13 uh, the answer in this case, because the answer is the 14 reason that there shouldn't be any adding in this equation is because 15 there isn't any flat fee being added. 16 So 1350 shouldn't be added on three shouldn't be added on because that would 17 just be adding $3 at the end of whatever total this amounts 18 to and adding three Z would simply be adding three 19 times the number of hours, which doesn't really make sense. 20 The only way this equation should be written is by multiplying Z the number 21 of hours by three, and then multiplying that by 1350, 22 because Tanya earns 13, 50 times the amount of hours she works. 23 So that's why the answer is.