Search found 210 matches


On method could be counting the number of ways of selecting the three coins. S => selected n => not selected $2 _ $2 __ $1 _ $1 __ Total S __ S __ S __ n __ = $5 S __ S __ n __ S __ = $5 S __ n __ S __ S __ = $4 n __ S __ S __ S __ = $4 Total # of ways = 4 # of ways he will exactly extract $5 = 2 P(...

by niketdoshi123

Fri Aug 24, 2012 3:47 am
Forum: Problem Solving
Topic: Probability of $5
Replies: 12
Views: 1167

Hi everyone, I've asked this question before and was given understandable solutions. However, I would like to know whether the below ways works for this type of problem:- A certain population of bacteria doubles every 10 minutes. If the number of bacteria in the population initially was 10^4, what ...

by niketdoshi123

Fri Aug 24, 2012 1:59 am
Forum: Problem Solving
Topic: Population - OG-2nd Edition
Replies: 3
Views: 1014

I need someone to explain the logic in this sentence "Since both are walking towards each other, the sum of their speeds are 6+5=11 miles/hr. Thank you This question tests the concept of relative speed. When two people/objects travel in opposite direction, either towards each other or away from eac...

by niketdoshi123

Thu Aug 23, 2012 3:42 am
Forum: Problem Solving
Topic: Manhattan GMATPREP
Replies: 3
Views: 849

If x, y, and z are three integers, are they consecutive integers? (1) z – x = 2 (2) x < y < z OA is C If x, y, and z are three integers, are they consecutive integers? (1) z – x = 2 (2) x < y < z OA is C statement 1: z-x = 2 we don't know anything about y let z = 4 since z - x = 2 , x = 2 y can...

by niketdoshi123

Wed Aug 22, 2012 7:16 pm
Forum: Data Sufficiency
Topic: XYZ
Replies: 3
Views: 1110

When positive integer A is divided by positive integer B, the result is 4.35. Which of the following could be the remainder when A is divided by B? A) 13 B) 14 C) 15 D) 16 E) 17 [spoiler]Ans: B)[/spoiler] My approach is as follows: A/B = 4.35 A/B = 4 + 0.35 = 4 + (35/100) = 4 + (7/20) However, I am...

by niketdoshi123

Sat Aug 18, 2012 12:48 am
Forum: Problem Solving
Topic: Divisibility and Primes
Replies: 5
Views: 1815

How many integers 'n' are there such that r<n<s ? (1) s-r=5 (2) r & s are not integers In the OG Quant guide, the ans is given as C. In my opinion, the ans should be E. Plz suggest. combining both the statements r & s are not integers So let s = 6.5 s-r = 5 (from the first statement) => r = 6.5 - 5...

by niketdoshi123

Wed Aug 15, 2012 9:14 am
Forum: Data Sufficiency
Topic: Arithmetic Properties of numbers
Replies: 9
Views: 969

This question is from jeff sackmann's 1000 problem set, which is superb. I know I can solve this by plugging in numbers, and that's actually the explanation that jeff gives. But I want to know how to do it algebraically. I tried figuring it out but couldn't get to the right answer. Hayden began wal...

by niketdoshi123

Tue Aug 14, 2012 11:06 pm
Forum: Problem Solving
Topic: How to solve this distance problem algebraically?
Replies: 3
Views: 937

While selling, a businessman allows 40% discount on the marked price and there is a loss of 30%. If it is sold at the marked price, profit percent will be (A) 10% (B) 20% (C)16 2/3 % (D)16 1/3% Pick number Let the marked price be $100 Price after 40% discount = $100 - 40%of $100 = $60 loss = (CP - ...

by niketdoshi123

Tue Aug 14, 2012 10:47 pm
Forum: Problem Solving
Topic: profit and loss
Replies: 3
Views: 4839

please help needed You chose option D, so I assume that you know how statement 2 is sufficient to answer.. I'll prove how statement 1 is not sufficient Question : was the total price of the merchandise in the two orders > $499 Statement 1: The delivery fee for one of the two orders was $3. The maxi...

by niketdoshi123

Tue Aug 14, 2012 9:33 pm
Forum: Data Sufficiency
Topic: delivery cost
Replies: 2
Views: 832

Matt gets a $1,000 commission on a big sale.This commission alone raises his aver-age commission by $150.If Matt's new average commission is $400,how many sales has Matt made? - I found the solution like this: "s= total number of things sold (before big sale) It should be total commission on the pr...

by niketdoshi123

Mon Aug 13, 2012 11:24 pm
Forum: Problem Solving
Topic: Matt needs help!
Replies: 2
Views: 1010

gmatwin wrote:If we use the formula: n(GUT)=n(G) + n(T) - n(G intersection T)

n(GUT)=30
n(G)=20
n(G intersection T)=15

By the formula,n(T) is 25.

Why this approach is wrong?
This approach is not wrong..
n(T) = n(only T) + n(G∩T)
=> n(only T) = n(T) - n(G∩T) = 25 - 15 = 10

by niketdoshi123

Sun Aug 12, 2012 5:10 am
Forum: Problem Solving
Topic: Overlapping sets
Replies: 7
Views: 2494

Hello, This is from MGMAT Strategy Guide. However, there is no solution given: 30 people are in a room. 20 of them play golf. 15 of them play golf and tennis. If everyone plays at least one of the two sports, how many of the people play tennis only? My approach is as follows: Tennis No Tennis Total...

by niketdoshi123

Sun Aug 12, 2012 12:12 am
Forum: Problem Solving
Topic: Overlapping sets
Replies: 7
Views: 2494

Hello, Can you please help with this problem? I was not clear with the explanation given in the book. The average number of students per class at School X is 25 and the average number of students per class at School Y is 33. Is the average number of students per class for both schools combined less...

by niketdoshi123

Sun Aug 12, 2012 12:06 am
Forum: Data Sufficiency
Topic: Weighted averages
Replies: 7
Views: 3421

Hello, Tickets to a play cost $10 for children and $25 for adults. If 100 tickets were sold, were more adult tickets sold than children's tickets? 1) The average revenue per ticket was $18 2) The revenue from ticket sales exceeded $1750 # of children tickets = c # of adult tickets = a a+c = 100 Tot...

by niketdoshi123

Sat Aug 11, 2012 11:56 pm
Forum: Data Sufficiency
Topic: Weighted Averages
Replies: 4
Views: 1696

Hello, This is from MGMAT Geometry Strategy Guide: The side of an equilateral triangle has the same length as the diagonal of a square. What is the area of the square? 1) The height of the equilateral triangle is equal to 6root3 2) The area of the equilateral triangle is equal to 36root3 OA: D I am...

by niketdoshi123

Sat Aug 11, 2012 11:44 pm
Forum: Data Sufficiency
Topic: Geometry Strategies - Triangle and Square
Replies: 2
Views: 932