GRE Math Formulas Flashcards
(115 cards)
Distance =
Rate*time
Average rate?
Total distance/ total time
or
Total earnings/ Total time
Work =
Rate * time Work= individual rate • number of workers • time
Difference of squares
X2 -Y2 = (x+y)(x-y)
(X+Y)2
X2 +2xy+y2
45-45-90 triangle
1:1: root 2
30-60-90 triangle
1:square root of 3: 2
Diagonal of a rectangular box
D squared = L squared + W squared + H squared
Height of equilateral triangle
H=S * sq. root of 3/ 2
SA of cube
6(side)2
Volume of cube
(Side)3
Volume of rectangular box
L*W*H
Arc length =
Sec angle/360 * 2(pi)(R)
Volume of circular cylinder
(Pi)(r2)(H)
Path. Triangle shortcut
5-12-13 3-4-5 8-15-17 7-24-25 9-12-15
Surface area of box
2(L*w)+2(h*L)+2(h*w)
Area of a trapezoid
A=(b1+b2)/(2)
Area of a polygon
A=B(H)
Sum of angles
180(N-2)
Is it possible for 2 events to happen at the same time? Yes.
P(a) or p(b) = p(a)+p(b) - p(a and b)
Is it possible for two events to happen at the same time? No.
P(a) or p(b) = p(a)+p(b)
When one event happens does this influence/change the outcome of the other? Yes.
P(a and b) = p(a) • p(b|a)
When one event happens does this influence/change the outcome of the other No.
P(a and b) = p(a) • p(b)
Area of polygon with diagonals
A= D1+D2/2