I will love you forever if.....(SAT Math)

Divyesh3e
Mon, 20 Jan 2014 11:19:21 +0000

Think of math as a game, once you know the rules, you can get points every time. The math section is far from challenging if you know the strategies and various formulas.

Few thngs to remember


SAT test writes love to use variables (x, y, etc…). Whenever I see a variable, I usually plugin a number that fits their description. It doesnt matter how hard the question is. Just look at the following example, that is deemed difficult according to CB themselves.


Example(level 4 math question from 2011):

a <b<c<d<e
p = abcde

In the inequality above and the equation above, a,b,c,d,e are positive integers. When just one of these integers is increased by 1 and multiplied by the other four, the new product is n. The difference (n-p) is greatest when which of the five integers is increased by 1:

(I decided to plug in a few numbers so that the inequality above would be true, the numbers can be anything).

a = 1
b = 2
c = 3
d = 4
e = 5

p = 120 (according to the equation)

It says that we have to add 1 to one of the 5 variables. After that, the new product of all the numbers will be n. Since it says the difference between n and p are greatest, n has to be the biggest possible number…

a = 1
b = 2
c = 3
d = 4
e = 5 + 1

n = 144 (Thats better than 120, but lets try adding one to another variable to see what happens)
I added +1 to d to get 5. 55421 = 150.

The pattern seems to be that as I add 1 to the smaller variables, n gets bigger. So I tried adding 1 to a, and it was 240.
The answer is therefore a.


Remember that somethng perpendicular to a line is the negative recriprocal of the slope. Its a simple concept, but I see this tested on almost every single test.


Example:

Line b is graphed on the plane above. What is the slope that is perpendicular to this line:

First you just find the slope of b (say it is 4x)

then we just add a negative sign and find the recriprocal. So the answer is -1/4x


Triangles/Geometry rules that show up very often:
All triangles add up 180 degrees
A straight angle is also always 180 degrees.
Bisect means the angle is cut in half