Search found 15 matches
I can hardly see any place for confusion in this question. I find it clear enough: there are 12 socks and 12 shoes, each sock and shoe corresponds to only one leg. On each leg, the sock must be put on before the shoe. Nowhere does it state that ALL the socks must be put before you start putting shoe...
- by armand_h
Tue Aug 07, 2012 4:10 am- Forum: Problem Solving
- Topic: Permutations - Need help
- Replies: 12
- Views: 4995
you can do some checks before you start solving equations: for example a very quick check is to set r to zero and check the results for each suggested solution. We know that with r=0 the to total area will be the are of the square, which in this case is(40/4)^2=100 You will notice very quickly that ...
- by armand_h
Tue Aug 07, 2012 2:21 am- Forum: Problem Solving
- Topic: 40 meter wire
- Replies: 2
- Views: 922
A=3P, this implies that A is a multiple of 3, but all suggested solutions are multiple of 3, so this doesn't help. A+13=2N-1, this implies that A is an even number, so the solution will be either 12, 36 or 42. let's start with 12 this will give us the following age pairs: today (12,4), in 13 years (...
- by armand_h
Tue Aug 07, 2012 2:03 am- Forum: Problem Solving
- Topic: al's age
- Replies: 3
- Views: 1286
there are twice as many K pencils as L, this means that K+ L is a multiple of 3. Which implies that 32-J is a multiple of 3. The only 2 solutions that match this criteria are 14 and 20. Let's check when J=20, K=8 and L=4 total price= 20*0.05+8*0.1+4*0.25=1+0.8+1=2.8 So J=20 is not the solution, the ...
- by armand_h
Tue Aug 07, 2012 1:42 am- Forum: Problem Solving
- Topic: need a simple solution
- Replies: 3
- Views: 1253
so if we have 8 letters A, B, C, D, E, F, G and H, how many permutations do we have, where ABC is before DEF. Step 1: compute the total number of permutations: 8! Step 2: Now we need to know the number of permutations where ABC is before DEF. There will be an identical number of permutations where A...
- by armand_h
Fri Aug 03, 2012 3:23 am- Forum: Problem Solving
- Topic: Permutation HELP
- Replies: 6
- Views: 2842
you can also do the following: with 12 cards you can form 6 pairs of identical cards: P1, P2, P3, P4, P5, P6 Once you have one pair of identical cards, you are left with 10 cards made up of only 2 suits of 5 cards each. with these 10 cards you can make 45 combinations of 2 cards 10C2=45. The 45 comb...
- by armand_h
Wed Aug 01, 2012 12:30 am- Forum: Problem Solving
- Topic: Combinations Randolph Question - Need expert help
- Replies: 8
- Views: 2011
P(x4) = 1- P(not x4)
P (not x4) is equal to:
probability that the 1st number is odd and the second is not 4
or
the 1st number is even (but not 4) and the second is odd
=3/6*5/6 + 2/6*3/6
=21/36
P(x4)=1-21/36=15/36
- by armand_h
Tue Jul 31, 2012 12:45 am- Forum: Problem Solving
- Topic: Set of numbers
- Replies: 2
- Views: 1025
Let's replace the women with numbers from 1 to 8 for example: |5|6|7|8| |1|2|3|4| to compute the number of combinations with increasing left to right and bottom to top, you need to fill the table below from 1 to 8 starting from left to right and bottom to top: |x|x|x|x| |x|x|x|x| for example: |3|x|x...
- by armand_h
Mon Jul 30, 2012 8:15 am- Forum: Problem Solving
- Topic: No. of ways - P&C
- Replies: 4
- Views: 1668
The choices were posted by GMATGuruNY, post Mon Jul 23, 2012 5:59 pmtheCEO wrote:Where do you see the choices?armand_h wrote:let's set P the price per person excluding gratuity
then
15*P*115/100=207
1.5*11.5*P=207
which means P should be a multiple of 4
the only solution that is multiple of 4 is 12
Correct answer B
- by armand_h
Mon Jul 30, 2012 12:03 am- Forum: Problem Solving
- Topic: Having trouble understanding this % problem (OFG13 #135)
- Replies: 8
- Views: 1746
let's set P the price per person excluding gratuity
then
15*P*115/100=207
1.5*11.5*P=207
which means P should be a multiple of 4
the only solution that is multiple of 4 is 12
Correct answer B
- by armand_h
Thu Jul 26, 2012 6:48 am- Forum: Problem Solving
- Topic: Having trouble understanding this % problem (OFG13 #135)
- Replies: 8
- Views: 1746
Is there an alternative way to solve this? Here is an alternative x and y are positive numbers, y>=x (A alone will take more time than A with B) time for B >=x (B alone will take more time than B with A) (A) x/(x+y) (B) y/x+y (C) xy/(x+y) (D) xy/(x-y) (E) xy/(y-x) (A) x/(x+y) it's deviding time by ...
- by armand_h
Thu Jul 26, 2012 5:45 am- Forum: Problem Solving
- Topic: RTW (nails)
- Replies: 14
- Views: 7306
* Probability of n(n+1) being multipole of 3 It's the probability of n being multiple of 3 or n+1 being a multiple of 3 =P(n)+P(n+1)=2*P(n) P(n)=1/3 (out of 3 consequitive integers one is multiple of 3) The answer is 2/3 * Probability of n(n+1)(n+2) being multiple of 8 It's the probability that n is...
- by armand_h
Thu Jul 26, 2012 1:44 am- Forum: Problem Solving
- Topic: probability
- Replies: 11
- Views: 5066
to simplify things, let's divide a and b by 10 A small, rectangular park has a perimeter of 56 feet and a diagonal measurement of 20 feet. What is its area, in square feet? 192 196 200 204 208 The answer is either 192 or 196: The maximum surface is when it's a square, surface= diagonal^2 / 2 =20*20/...
- by armand_h
Thu Jul 26, 2012 1:21 am- Forum: Problem Solving
- Topic: Rectangular park
- Replies: 6
- Views: 1611
a+b+c=x+y+z, with x, y and z being the opposite angles to a, b and c resp.
knowing that a+b+c+x+y+z=360, then a+b+c=360/2=180
- by armand_h
Thu Jul 26, 2012 12:08 am- Forum: Problem Solving
- Topic: Geometry
- Replies: 8
- Views: 1213
You don't need to count. Here is another way to think of it. The number of 2 similar digits between 700 and 999 is 3 times the number of similar digits between 700 and 799 So the answer is in the form of 3N-1 (the -1 is because we have to exclude 700) Which means if you add 1 to the answer it will b...
- by armand_h
Wed Jul 25, 2012 9:11 am- Forum: Problem Solving
- Topic: Counting integers
- Replies: 10
- Views: 8726