# Shared Flashcard Set

## Details

GMAT - Problem Solving
Problem Solving Section of 12th ed review
41
03/06/2011

Term
 Mean
Definition
 Average
Term
 Median
Definition
 Center number (or average of 2 center numbers for even set)
Term
 Mode
Definition
 The number that occurs most frequently
Term
 Range
Definition
 The greatest value in the set minus the least value.
Term
 Standard Deviation
Definition
 Gen: is greater the more data are spread away from the mean. For each number in set, X, (x-mean)2. Add the sum of these numbers.
Term
 Frequency distribution
Definition
 For each data value in a set, counting the number of its frequency.
Term
 Set: intro
Definition
 A collection of numbers or other objects. S={5,-1,0}; ABS(s)=3. A set can also be a subset of another set.
Term
 Set: Union
Definition
 The elements that are in a OR in b OR in both. Denoted as: aUb
Term
 Set: Intersection
Definition
 All elements that are contained in both a AND b. The shaded, shared part of a venn diagram. Denoted by A∩B.
Term
 Set: number in union
Definition
 for sets S and T, the number of elements in their union (U)= ABS(SuT)=ABS(S)+ABS(T)-(SnT). The intersecting numbers are subtracted so that they aren't counted twice.
Term
 Set: disjointed
Definition
 Two sets are disjointed or mutually exclusive if they share no elements. Thus, ABS(SuT)=ABS(S)+ABS(T).
Term
 Factorial
Definition
 example: 3!=1*2*3=6
Term
 Factorial for counting combinations
Definition
 Factorials are useful for the ordering of objects, or permutations (i.e. combinations for A,b,c). N!=N+(N-1)+(N-2), etc. Permutation is a selection process in which objects are selected one by one in a certain order.
Term
 Permutation
Definition
 For a set of objects (n) where only some (k) are selected, and order doesn't matter. The number of possible complete selections of k objects is the # of combinations of n objects taken k at a time, denoted by (n over k). (n over k)=(n!)/((k!)(n-k)!). or (5 over 2)=5!/(2!3!)=120/(2*6)=10.
Term
 Permutation, cont.
Definition
 (n over k)=(n over (n-k)). Because every set chosen corresponds to a set not chosen. (5 over 2)=10=(5 over 3).
Term
 Discrete probability of an event
Definition
 P(E)=(the number of outcomes in E)/(the total number of possible outcomes).
Term
 Outcomes of experiment with two events
Definition
 For experiment with events E and F: "not E" - set of outcomes that are not outcomes in E. "E or F" - the set of outcomes in E or F or both; union; EUF. "E and F"- outcomes in both E and F: intersection; EnF.
Term
 E does not occur
Definition
 P(not E)=1-P(E)
Term
 E or F
Definition
 P(E or F)=P(E)+P(F)-P(E and F). If "E and F" is impossible, then it equals 0.
Term
 Independent events
Definition
 P(E and F)=P(E)P(F). Because they are independent, the order of the events does not matter.   P(E or F)=P(E)+P(F)-P(E)P(F).
Term
Definition
 ax2+bx+c=0
Term
Definition
 x=-b ± √(b2-4ac) /2a
Term
 Solving for inequalities
Definition
 The same as solving an equation, except that div. or mult. by a neg number reverses the sign.
Term
 Function
Definition
 An expression denoted by f(x), and the variable is given a value. In any function there can be no more than one output for any given input.
Term
 GEOMETRY - intersecting lines
Definition
 any two straight lines that intersect; the opposite angles have the same measure. Two angles on a straight line add up to 180 deg.
Term
 Polygon
Definition
 a closed plane figure formed by three or more line segments. The interior angles of a triangle =180. The int. ang. of a polygon with n sides = (n-2)*180.   [image]
Term
 Triangles
Definition
 The sum of the lengths of any two sides is greater than the length of the third.
Term
 Equilatoral/isoceles triangle
Definition
 Equilatoral - all sides same length Isocelese - at least two sides the same length If two sides are same length, then two angles opposite those sides have same measure.   [image]
Term
 Right angle triangle
Definition
 Hypoteneuse is the side opposite the right angle (c). Ratio of 3:4:5 is right triangle. Thus, a2+b2=c2   [image]
Term
 Triangle ratios
Definition
 45-45-90 tri: lengths are 1:1:√2 30-60-90 tri: lengths are 1:√3:2
Term
 Triangle areas
Definition
 area=(height X base)*(1/2)   [image]
Term
 Parallelogram
Definition
 Quadrilateral with two sets of parallel lines. The opposite sides are of equal length. Area = base x height [image]
Term
 Trapezoid
Definition
 Two sides are parallel (but other two are not). Area=(.5)(top+bottom)(height)   [image]
Term
 Circle
Definition
 Circumference = 2Πr Area = Πr2 Deg=360
Term
 Arc within a circle
Definition
 Length of arc is x(deg)/360 of the circumference of circle. If x=60, arc is 60/360 * circumference.   [image]
Term
 Triangle in circle
Definition
 If a triangle in a circle has one side on the diameter, then the circle is a right triangle.
Term
 Rectangular solid
Definition
 Vertex: point where two edges meet. Rec solid has 6 faces, 12 edges, and 8 vertices. Surface area = sum of all areas of faces. Volume = LxWxH
Term
 Cylinder
Definition
 Two base circles are the same size. Surface area = 2(Πr2)+2ΠrH Volume=Πr2*H   [image]
Term
 Coordinate plane
Definition
 four quadrants; the center is the origin.   [image]
Term
 Equation of a line
Definition
 y=mx+b m= slope= (y2-y1)/(x2-x1) b= y-intercept (value when x=0) To find x-int must set y=0 and solve for x.   After establishing the slope, plug a known coordinate on line into equation to find the equation of the line.
Term
 Two linear equations
Definition
 If unique solution, then cross at a single point.If equations are equivalent, then they are the same line.If no solution, the two lines are parallel and do not intersect.
Supporting users have an ad free experience!