Explanation for Question 31 From the Math (Calc) Section on the Official Sat Practice Test 10
Now for question number 31, we're told that Lynn has $8 to spend on 2 apples and oranges and apples is going to cost 65 cents. 3 Each and orange will cost 75 cents each there's no task. 4 So are buying five apples. What is the minimum number of whole oranges she 5 can buy? Right? And so we're told right off the bat that we're buying 6 five apples and each apple is going to cost 65 cents. 7 And we don't know how many oranges we're buying. 8 So I'll put a variable there. Why each one is going to cost 75 cents. 9 And we're told she has $8 suspend total. So when I add the cost, 10 you know, the total cost of each of my fruits, 11 my apples and oranges, I should get a total cost of eight. 12 So we're on the calculator section here. So you can just plug everything into 13 our calculators. We've got five times 0.6, 14 five, five times 0.6, 15 five, that's equal to 3.25. 16 Plus Y times 0.75 is equal to eight. 17 So I'll subtract 3.25 from both sides. 18 And I'll get Y times 0.75 is equal to eight minus 3.25. 19 That is 4.75 now to solve for Y which again 20 is my number of oranges. I'll divide both sides by 0.75. 21 This cancels and tells me that Y is equal to 6.33, 22 three. Right? So supposedly she could by 6.3, 23 three oranges. So six oranges, 24 seven oranges she's in between. That's what she can afford, 25 but can you buy 0.3 of an orange? 26 No. Right. So she either has to buy six or she has to buy 27 seven, but look, her number that she can afford is below seven, 28 seven would cost her more than $8. 29 So she can't afford seven. She has to go down and she can only 30 afford six oranges.