Search found 11 matches
Thank you both, this is very helpful. So just to confirm I understood this, let's say if I want to find the probability that the first ball is black, given that second ball is black as well.
P(BB) = 2/5(Since two black balls) * 3/4(Since second is definitely black). = 3/10?
- by late4thing
Thu Oct 06, 2016 6:44 am- Forum: Problem Solving
- Topic: An basket contains 3 black balls and 2 red balls
- Replies: 8
- Views: 12342
Tough Probability
Suppose Mr. Smith goes to Vegas. He knows from previous experiences that the probability he will come out ahead after playing black jack is .3. The probability he will be ahead after playing the roulette wheel is .4. He also knows that his chances of coming out ahead in one game is independent of th...
- by late4thing
Wed Oct 05, 2016 5:18 pm- Forum: Problem Solving
- Topic: Tough Probability
- Replies: 2
- Views: 1852
An basket contains 3 black balls and 2 red balls
Treating this as 2 questions:
An urn contains 3 black balls and 2 red balls. Balls are selected one at a time without replacement.
Q1: What is the probability that the second ball is red?
Q2: What is the probability that the second ball is red, given that the first ball is black?
- by late4thing
Wed Oct 05, 2016 5:17 pm- Forum: Problem Solving
- Topic: An basket contains 3 black balls and 2 red balls
- Replies: 8
- Views: 12342
Tough PS - Number Properties & Exponents
For integers x, y, and z, if ((2^x)^y)^z = 131072 which of the following must be true ? A. The product xyz is even B. The product xyz is odd C. The product xy is even D. The product yz is prime E. The product yz is positive I can understand that the last digit will be odd (i.e. z = odd) but how to d...
- by late4thing
Wed Feb 17, 2016 8:43 pm- Forum: Problem Solving
- Topic: Tough PS - Number Properties & Exponents
- Replies: 5
- Views: 2328
Average Speed Tough DS
A cyclist rode up and down a mountain along the same route each way. What was his average speed for the full trip?
(1) His uphill speed averaged 22 kilometers per hour, and his downhill speed averaged 48 kilometers per hour.
(2) The route is 16 kilometers each way.
Source: VeritasPrep
- by late4thing
Sat Feb 13, 2016 1:49 pm- Forum: Data Sufficiency
- Topic: Average Speed Tough DS
- Replies: 8
- Views: 3202
How much is x percent of a certain number?
How much is x percent of a certain number?
(1) x = 60
(2) 2x percent of the number is 24
- by late4thing
Sat Jan 09, 2016 3:24 pm- Forum: Data Sufficiency
- Topic: How much is x percent of a certain number?
- Replies: 5
- Views: 3735
From 1965 on, the region's standard of living has soared,
From 1965 on, the region's standard of living has soared, but also unemployment and prices.
A. but also
B. and also
C. but so have
D. and so also
E. but so did
- by late4thing
Thu Nov 12, 2015 6:25 am- Forum: Sentence Correction
- Topic: From 1965 on, the region's standard of living has soared,
- Replies: 1
- Views: 3492
Is x2 greater than x ?
Is x2 greater than x ?
(1) x2 is greaer than 2x.
(2) 2x2 is greater than x.
Please explain using the Critical Points method.
- by late4thing
Fri Nov 06, 2015 11:35 am- Forum: Data Sufficiency
- Topic: Is x2 greater than x ?
- Replies: 2
- Views: 1803
astronomers had/have discovered 17 nearby stars
By 1999, astronomers had discovered 17 nearby stars that are orbited by planets about the size of Jupiter A: had discovered 17 nearby stars that are orbited by planet B: had discovered 17 nearby stars with planets orbiting them that were C: had discovered that there were 17 nearby stars that were or...
- by late4thing
Fri Oct 30, 2015 7:44 am- Forum: Sentence Correction
- Topic: astronomers had/have discovered 17 nearby stars
- Replies: 9
- Views: 8325
A sum of $200,000 from a certain estate was divided
A sum of $200,000 from a certain estate was divided among a spouse and three children. How much of the estate did the youngest child receive? (1) The spouse received 1/2 of the sum from the estate, and the oldest child received 1/4 of the remainder. (2) Each of the two younger children received $12,...
- by late4thing
Fri Oct 16, 2015 8:38 am- Forum: Data Sufficiency
- Topic: A sum of $200,000 from a certain estate was divided
- Replies: 3
- Views: 2643
Points P, R, M and S lie on the number line shown.
http://s17.postimg.org/p3ewc3zbv/line.jpg Points P, R, M and S lie on the number line shown. The coordinate of R is 0. The distance between P and R is 1/3 the distance between P and S. If M is the midpoint of line segment PS, what is the coordinate of P? (1) The coordinate of M is 1.5 (2) The coord...
- by late4thing
Thu Oct 15, 2015 2:17 pm- Forum: Data Sufficiency
- Topic: Points P, R, M and S lie on the number line shown.
- Replies: 6
- Views: 4470