Explanation for Question 19 From the Math (No Calc) Section on the Official Sat Practice Test 3
Now for number 19 in our first sentence, 2 we're told that each hamburger is 50 more calories than fries. 3 Now, if we write that out as an equation, we would say, see that 4 if we added 50 to fries, we would get the hamburger. 5 Right? And then in our second sentence, 6 we're told that two hamburgers and three fries have 1700 calories, 7 right? So if I add my two hamburgers, plus my three fries, 8 I'll get the 1700 and I'm asked for the calories and the hamburger, 9 right? So what I really want to do here is solve for H so 10 I'll start by manipulating this first equation. 11 So that rather than being solved for age, 12 it's solved for F so I can take this F plug it into my 13 bottom equation, and then I'll only have H's in that bottom equation, 14 which then will allow me to solve for H right? 15 So I have two H plus three times H minus 50 is equal to 16 1700. Now I can distribute this three here. 17 So I get two H plus three H minus one 50 is equal to 18 1700. And then I can combine like terms five 19 H minus one 50 is equal to 1700. 20 I'll add one 50 to both sides, which gives me five H is equal 21 to 1850. And then we can divide both sides by five. 22 And so likely you'll have to do long division to get that answer. 23 And when you do that long division, you get the H is equal to 24 370, which tells us that there are 370 calories in the 25 hamburger.