Search found 415 matches
If Enid and Topanga each roll a single ten-sided die (which has sides numbered 1 through 10), what is the probability
Problem Solving
Re: If Enid and Topanga each roll a single ten-sided die (which has sides numbered 1 through 10), what is the probabilit
Whatever number one rolls there's a 1/10 chance that the other rolls the same number and a 9/10 chance that the numbers are different.
Each has a 50% chance of rolling a larger number than the other when the numbers are different.
1/2*9/10 = [spoiler]9/20,B[/spoiler]
- by regor60
Mon Jan 31, 2022 12:20 pm- Forum: Problem Solving
- Topic: If Enid and Topanga each roll a single ten-sided die (which has sides numbered 1 through 10), what is the probability
- Replies: 1
- Views: 272
two strings have equal length. One of the strings is shaped, with no overlap, into a circle. The other string is shaped,
Problem Solving
Re: two strings have equal length. One of the strings is shaped, with no overlap, into a circle. The other string is sha
Source: GMAT Prep Two strings have equal length. One of the strings is shaped, with no overlap, into a circle. The other string is shaped, with no overlap, into a square. What is the ratio of the area of the region enclosed by the circle to the area of the region enclosed by the square? A. \(1 : 2\...
- by regor60
Mon Jan 17, 2022 12:52 pm- Forum: Problem Solving
- Topic: two strings have equal length. One of the strings is shaped, with no overlap, into a circle. The other string is shaped,
- Replies: 3
- Views: 373
Five people are running in a race. The first one to finish wins a gold medal, the second wins a silver medal and the thi
Problem Solving
Re: Five people are running in a race. The first one to finish wins a gold medal, the second wins a silver medal and the
Two of the five people won't win a medal.
How many ways to pick 2 losers out of 5?
5!/2!3! = 10. Notice that using combinations they are not being arranged.
The remaining 3 get medals and can be arranged 3! or 6 ways
Total ways for medals to be won
10*6=60,C
- by regor60
Fri Jan 07, 2022 9:39 am- Forum: Problem Solving
- Topic: Five people are running in a race. The first one to finish wins a gold medal, the second wins a silver medal and the thi
- Replies: 1
- Views: 320
A certain company assigns projects to employees such that more than one or no employee can work on any project. In how
Problem Solving
Re: A certain company assigns projects to employees such that more than one or no employee can work on any project. In h
To minimize confusion, this question should be rephrased to read:
"A certain company assigns projects to employees such that each project may be assigned any number of employees, including none. In how many ways can 3 employees be assigned to 4 projects ?"
- by regor60
Mon Jan 03, 2022 4:46 am- Forum: Problem Solving
- Topic: A certain company assigns projects to employees such that more than one or no employee can work on any project. In how
- Replies: 1
- Views: 285
Demetri has trouble spelling the word “banana.” Whenever he tries to spell the word, he writes the letters “ba,” then...
Problem Solving
Re: Demetri has trouble spelling the word “banana.” Whenever he tries to spell the word, he writes the letters “ba,” the
To spell banana correctly, he has to write "na" twice, in order, and then stop. The probability of the first "na" is 1. The probability of the second "na" is .6 Now, he needs to stop in order to spell the word correctly. There is a 40% chance of stopping after writing a...
- by regor60
Sun Jan 02, 2022 6:30 am- Forum: Problem Solving
- Topic: Demetri has trouble spelling the word “banana.” Whenever he tries to spell the word, he writes the letters “ba,” then...
- Replies: 1
- Views: 244
A botanist selects n^2 trees on an island and studies (2n + 1) trees everyday where n is an even integer. He does not
Problem Solving
Re: A botanist selects n^2 trees on an island and studies (2n + 1) trees everyday where n is an even integer. He does no
Poorly worded question. As worded, it states that 2K+1 trees are studied every day. Every day includes the last day, by definition, lol. This could lead to the natural short cut solution that since 2k+1 is always odd, 28, answer B cannot be the last day. The question leaves unsaid that the last day ...
- by regor60
Wed Dec 29, 2021 10:04 am- Forum: Problem Solving
- Topic: A botanist selects n^2 trees on an island and studies (2n + 1) trees everyday where n is an even integer. He does not
- Replies: 1
- Views: 304
Re: If x/y is an integer, which of the following must also be an integer?
Can X/Y be an integer if neither X nor Y are ? Well, setting X=1/2 and Y=1/4 means X/Y= (1/2)/(1/4)=2, so the answer is yes. This also means III is rejected as an answer. Is XY an integer ? 1/2*1/4 = 1/8, so no Is Y/X an integer ? No, it is (1/4)/(1/2) or 1/2 Answer choice E is the only one that fits
- by regor60
Sun Dec 26, 2021 9:58 am- Forum: Problem Solving
- Topic: If x/y is an integer, which of the following must also be an integer?
- Replies: 1
- Views: 203
Re: Which of the following is between \(\dfrac{13}{17}\) and \(\dfrac{17}{21}?\)
Adding 1 to the numerator and denominator of 13/17 yields 14/18, or 7/9.
Adding 1 to 13 is a greater percentage change to the numerator than adding 1 to 17 is to the denominator.
This must mean that 13/17 is slightly less than 7/9.
Answer choiceE would seem to be the best fit
- by regor60
Sun Dec 26, 2021 9:46 am- Forum: Problem Solving
- Topic: Which of the following is between \(\dfrac{13}{17}\) and \(\dfrac{17}{21}?\)
- Replies: 1
- Views: 168
If m is the product of all integers from 1 to 40, inclusive, what is the greatest integer p for which
Problem Solving
Re: If m is the product of all integers from 1 to 40, inclusive, what is the greatest integer p for which
5 is the largest prime that's a factor of 10, so should be the limiting part
5-20 has 4 fives
25 has 2
30-40 has 3
9 total
- by regor60
Mon Dec 20, 2021 12:59 pm- Forum: Problem Solving
- Topic: If m is the product of all integers from 1 to 40, inclusive, what is the greatest integer p for which
- Replies: 2
- Views: 671
How many different flags can be made from 4 colors- Red, Blue, Green, and White such that no color is repeated more than
Problem Solving
Re: How many different flags can be made from 4 colors- Red, Blue, Green, and White such that no color is repeated more
This question is poorly worded and as written doesn't provide an answer that matches any of the answer choices. "Repeated" means to occur more than once. Repeated no more than once could be interpreted as occurring at most twice, but wouldn't be written that way, regardless. The provided a...
- by regor60
Sat Dec 18, 2021 2:17 pm- Forum: Problem Solving
- Topic: How many different flags can be made from 4 colors- Red, Blue, Green, and White such that no color is repeated more than
- Replies: 1
- Views: 246
Re: Which value(s) of \(x\) satisfies the equation above?
Since I appears in all the answer choices but B, potentially eliminating this would immediately identify the answer:
Plugging in -1 into the right side:
(3*(-1^2)+13)^(1/2) = (3+13)^(1/2)=
16^(1/2) = 4
Does this result equal the left side?
2*-1 -2 = -4 > NO
AnswerB
- by regor60
Fri Dec 10, 2021 5:06 am- Forum: Problem Solving
- Topic: Which value(s) of \(x\) satisfies the equation above?
- Replies: 1
- Views: 242
In the above diagram, the 16 dots are in rows and columns, and are equally spaced in both the horizontal & vertical
Problem Solving
Re: In the above diagram, the 16 dots are in rows and columns, and are equally spaced in both the horizontal & vertical
Need 3 points for a triangle, but only 2 points can be collinear. Setting that issue aside for the moment, 3 points can be selected 16!/13!3! = 560 That's the maximum number of triangles, but we know a bunch won't work because some of the groups of 3 will lie on the same line. But we can eliminate C...
- by regor60
Wed Dec 08, 2021 5:02 am- Forum: Problem Solving
- Topic: In the above diagram, the 16 dots are in rows and columns, and are equally spaced in both the horizontal & vertical
- Replies: 1
- Views: 488
To graduate, John needs to complete eight courses. Of these eight, he must take only three science courses, only two...
Problem Solving
Re: To graduate, John needs to complete eight courses. Of these eight, he must take only three science courses, only two
He needs to take 8 courses in total, with 3+2+1=6 from the stated curriculum, leaving 2 other courses to be taken outside the stated curriculum. There are 5+6+4=15 courses available from the stated curriculum and 20 courses in total. So the 2 courses to be taken outside the curriculum can be selecte...
- by regor60
Sat Dec 04, 2021 2:12 pm- Forum: Problem Solving
- Topic: To graduate, John needs to complete eight courses. Of these eight, he must take only three science courses, only two...
- Replies: 1
- Views: 330
Susie can buy apples from two stores: a supermarket that sells apples only in bundles of 4, and a convenience store that
Problem Solving
Re: Susie can buy apples from two stores: a supermarket that sells apples only in bundles of 4, and a convenience store
If she buys 5 bundles of 4 apples from the supermarket, she needs 0,A apples from the convenience store
- by regor60
Thu Dec 02, 2021 5:07 pm- Forum: Problem Solving
- Topic: Susie can buy apples from two stores: a supermarket that sells apples only in bundles of 4, and a convenience store that
- Replies: 2
- Views: 318
Re: What is the value of \(5+4\cdot 5+4\cdot 5^2+4\cdot 5^3+4\cdot 5^4+4\cdot 5^5?\)
Let expression = S.
S/5 = 1+4+4*5+4*5^2+4*5^3+4*5^4
which equals
S-4*5^5
So, S/5 = S- 4*5^5.
S-S/5= 4*5^5
4/5S = 4*5^5
S= (5/4)*4*5^5= 5*5^5=[spoiler]5^6,A[/spoiler]
- by regor60
Mon Nov 29, 2021 7:06 am- Forum: Problem Solving
- Topic: What is the value of \(5+4\cdot 5+4\cdot 5^2+4\cdot 5^3+4\cdot 5^4+4\cdot 5^5?\)
- Replies: 2
- Views: 594