[Video] Q1: A painter will paint n walls with the same size and shape in a building using a specific brand of paint. the painter’s fee can be calculated by the expression nklh, where n is the number of walls, k is a constant with units of dollars per square foot, l is the length of each wall in feet, and h is the height of each wall in feet. if the customer asks the painter to use a more expensive brand of paint, which of the factors in the expression would change?

Explanation for Question 1 From the Math (No Calc) Section on the Official Sat Practice Test 3

Now number one says that a painter will paint and walls with the same 2 size and shape using a specific brand right in the fee can be calculated 3 from this expression here. And then it tells us the N 4 is the number of walls. K's a constant with the units dollars per square 5 foot. When it says the case a constant, 6 it just means that it's a normal number. And that that number is never 7 going to change. It'll always be the same number and then height or H 8 is the height. If a customer asks, 9 um, the painter to use a more expensive brand, 10 which of the following would change, right? So if we're using a more expensive 11 brand of paint, that's not going to change the height of the wall, 12 right? That's not changing the wall at all. It's also not changing the length 13 of the wall right now. K is a constant. 14 And if we know the definition of constant here, 15 it's the units of dollars per square foot. 16 Right. And if you're changing to a more expensive paint, 17 you're going to be paying more dollars per square foot. 18 Right? And so with that in mind, that means that K is going to 19 be our answer here because K is the only variable that relies 20 on the price of the paint. And so our best answer is C.