GMAT Quant Flashcards
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| 409651705 | What is the formula to calculate the area of a triangle with the following vertices L(1,3), M(5,1), and N(3,5)? | 1/2 [X1(Y2-Y3) + X2(Y3-Y1) + X3(Y1-Y2)] | |
| 409651706 | In Exponential Growth, a quantity is...? | is multiplied by the constant each period of time:Y(t)= Yo * k^t | |
| 409651707 | If K is the constant difference between successive terms, and x is some other constant, then provide formulas: | Direct formula Sn= kn + x Recursive formula Sn=sn-1 + k S1=k+x | |
| 409651708 | Is there a condition on when to multiple or divide an inequality by a variable? | You cannot multiple or divide an inequality by a variable, unless you the sign of the number of that the variable stands for. | |
| 409651709 | Quadratic equations with one solution - also called perfect square. Solve: X^2 +8x + 16=0 | (x+4) (x+4) = 0 (x+4)^2= 0 The only solution for x is -4 | |
| 416229935 | How many distinct prime divisors does a positive integer N have? 1. 2N has one prime divisor 2. 3N has one prime divisor | Answer: C 1. N has no prime divisor or N has only digit 2 as a prime divisor/factor.... 2, 4, 8 2. Same as 1 | |
| 416229936 | Vertices of a triangle have coordinates (1,0), (4,0) and (0.A). Is the area of the triangle bigger than 15? 1. A<3 2. The triangle is right | B stmt 2: if the given triangle is right angle then one side which forms the hypotenuse is 5 so the other two sides will be less than 4. so definitely area of triangle has to be less than 15 | |
| 416229937 | What is the mean of four consecutive even integers a,b,c,d? a is the smallest of the four integers. 1. a+d = b + c 2. b+c =d - a | B Ste 2: as they are consecutive the condition b+c = d-a is equal to a+2 + a+4 = a+6 - a -> a=0 | |
| 416229938 | When dividing two number and result contains a remainder, such remainder is always smaller than denominator. | e.g. 5/10 -- remainder = 5 (10>5) 25/10 -- remainder - 5 ( 5<10) | |
| 416229939 | X, A, B and are positive integers. When X is divided by A, the remainder is B. If when X is divided by B, the remainder is A - 2, which of the following must be true? (A) A is even (B) X + B is divisible by A (C) X - 1 is divisible by A (D) B = A - 1 (E) A + 2 = B+1 | D When dividing two number and result contains a remainder, such remainder is always smaller than denominator. e.g. 5/10 -- remainder = 5 (10>5) 25/10 -- remainder - 5 ( 5<10) | |
| 416229940 | Foodmart customers regularly buy at least one of the following products: milk, chicken, or apples. 60% of shoppers buy milk, 50% buy chicken, and 35% buy apples. If 10% of the customers buy all 3 products, what percentage of Foodmart customers purchase exactly 2 of the above products? (A) 5% (B) 10% (C) 15% (D) 25% (E) 30% | Use this equations: 1. b1 + 2b2 + 3b3 = 145% 2. b1 + b2 + b3 = 100% 2. b3= 10% | |
| 416229941 | In an exponential (or geometric) sequence, the ratio between successive terms is always the same. Provide formula(s) | Direct Formula Sn=xk^n Recursive Formula Sn=kSn-1 S1=xk | |
| 416234143 | What's the area of a Trapezoid? | [(Base1 + Base2)*Height]/2 | |
| 416234144 | What's the area of a Parallelogram? | Base * Height | |
| 416234145 | What's the area of rhombus? | ( Diagonal1 * Diagonal2) / 2 | |
| 416234146 | What is the Surface Area? | The SUM of the areas of ALL of the faces | |
| 416234147 | IF TWO similar triangles have corresponding side lenghts in ratio a:b, then their areas will be in ratio of? | a^2:b^2 | |
| 416234148 | For similar SOLIDS with corresponding sides in ratio a:b their volumes will be in ratio of? | a^3:b^3 | |
| 416234149 | perpendicular lines have what kind of reciprocal slope? | perpendicular lines have negative reciprocal slopes | |
| 416234150 | Transalte: Jane bought twice as many apples as bananas | A=2B | |
| 416234151 | Work rate= given # of jobs/ given amount of time | Always express work rates as jobs per unit time, not as time/job | |
| 416234152 | Of all quadrilaterals with a given perimeter which one has the largest area and which one has the minimun perimeter? | The square | |
| 416234153 | what's the general probability formula? | # of desired or successful outcomes / Total # of positive outcomes | |
| 416234154 | If a coin is tossen 3 times, what is the probability that it will turn up heads exactly twice | 3/8 - you can use the counting tree method to figured it out | |
| 416234155 | And means what in probability? | And means multiply the probabilities. You'll wind up w/ a smaller number, which indicates a lower probability. | |
| 416234156 | OR means what in probability? | Means add the probabilities. You'll wind up w/ a larger # | |
| 416234157 | Explain this formula: P(A) + P(B) - P(A and B) | This formula works for all OR problems. However, it is a waste of time for problems in which events A and B cannot occurred together, b/c then P(A and B)=0 | |
| 416234158 | When should you use the 1 - X probability trick | When the success contains multiple probabilities - especially, if the wording contain phrases such as "AT LEAST" and "AT MOST" then consider finding the probability that success does not happen. | |
| 416235163 | "Y percent less than" can be translated as what? | 1 - (Y/100) | |
| 416235164 | Is X | Yes, when X and Y are positive OR negative. Otherwise, when X is negative and Y is positive: 1/x< 1/y | |
| 416235165 | If x>y, x<6, and y>-3, what is the largest prime number that could be equal to x+y? | A=11 --> there is no integer constraint | |
| 470036236 | A rabbit on a controlled diet is fed daily 300 grams of a mixture of two foods, food X and food Y. Food X contains 10 percent protein and food Y contains 15 percent protein. If the rabbit's diet provides exactly 38 grams of protein daily, how many grams of food X are in the mixture? | Ans:0.10X + 0.15(300 - X) = 0.38 .... 140 | |
| 470036237 | Does the integer k have a factor p such that 1 | Answer B:
1 - if, for example, k=29 then p could not have a factor of p....
2. for each number of k from 13! +2 to 13! + 13 there is a factor p such that 1| | |
| 470056911 | reciprocals numbers | To determine if two number are reciprocals multiple the numbers in question; if this multiplication yields 1 then these numbers are reciprocals. For example, (Sqrt 7) / 2 and [2*(Sqrt 7)] / 7 (Sqrt 17) - 4 and (Sqrt 17) + 4 | |
| 470125810 | How many of the three-digit numbers are divisible by 7? (A) 105 (B) 106 (C) 127 (D) 128 (E) 142 | Divide all of the three-digit numbers 999-100+1=900 (Don't forget to add 1 to get the number of all the 3-digit numbers) by 7, which is 128.57, and then round it off to 128. |