Search found 12 matches
am not able to get this equation (10%*4 + 100%* x) / (4+x) = 25% .......specifically 100%*x Hello Aspirant1, This is similar to weighted average. see in the numerator 10% of 4 gallons will give you the content of water in 4 gallons and 100% of x gallons will contain total water which has to be mixed...
- by nikilnikil
Sun Nov 29, 2009 8:48 pm- Forum: Problem Solving
- Topic: plz answer this mixture problem
- Replies: 8
- Views: 2823
cheeseburst,
your point is valid. There is no limit for the maximum value of range, though on GMAT, the question is targeted more on the minimum range of the group. IF it is targeted at maximum range, then you have to choose the maximum value provided in the answer choice.
~Nik
- by nikilnikil
Wed Nov 25, 2009 10:22 pm- Forum: Problem Solving
- Topic: combined range of 2 Sets ?
- Replies: 7
- Views: 4587
you can easily solve such problems using "AP-arithmetic progression" formula, if you are not able to solve using the above mentioned method. Tn=a+(n-1)d Tn=last term a= first term n=number of terms d= difference between terms In the above case series is something like 2,4,6,..........198 S...
- by nikilnikil
Wed Nov 25, 2009 6:40 pm- Forum: GMAT Math
- Topic: sum of all even numbers from 99 to 301
- Replies: 19
- Views: 80453
this expression is of the form
(a+b)^2 = a^2+b^2+2*a*b
sqrt(9+sqrt(80)) ^2 + sqrt(9-sqrt(80))^2 + 2* sqrt((9+sqrt(80))*(9-sqrt(80))
= 9+sqrt(80) + 9 - sqrt(80) + 2 * (81-80) [because (a+b)(a-b) = a^2 -b^2]
=9+9+2 = 20
~Nik
- by nikilnikil
Wed Nov 25, 2009 12:47 am- Forum: Problem Solving
- Topic: Evaluating radical expressions - Please Help ASAP
- Replies: 3
- Views: 2170
this has to be calculated using brute force the squares which are below 75 are 1 4 9 16 25 36 49 64 lets take largest number first 64 , remaining 75-64 = 11 cannot be expressed as sum of 2 squares. 49, reamining 75-49 = 26 = 1 + 5*5 . This is the solution. so, 1,5,7 are the three numbers 1+5+7 = 13 ...
- by nikilnikil
Tue Nov 24, 2009 11:32 pm- Forum: Problem Solving
- Topic: q 108) from 198 700 level questions
- Replies: 5
- Views: 2537
Hello, That 2% 14% 34 % ( mean ) 34 % 14% 2% is a standard percentage for normal deviation. so the curve will be standard on both the sides of a inverted parabola. mean at the center and the parabola is divided into 6 parts. 3 parts towards the left of mean and 3 parts towards right of mean. one par...
- by nikilnikil
Tue Nov 24, 2009 8:31 pm- Forum: Data Sufficiency
- Topic: very challenging problem
- Replies: 3
- Views: 1201
- by nikilnikil
Tue Nov 24, 2009 1:48 am- Forum: Problem Solving
- Topic: combined range of 2 Sets ?
- Replies: 7
- Views: 4587
Good question: In a normal distribution curve, the distribution will be 2% 14% 34% | 34% 14% 2% The question is asking about the least 16% of population (.. it is asking for 2 Standard deviation less than the mean ). So we have to find the SD. In total, the question is asking , which information is ...
- by nikilnikil
Tue Nov 24, 2009 1:44 am- Forum: Data Sufficiency
- Topic: very challenging problem
- Replies: 3
- Views: 1201
combined range of 2 Sets ?
Set X has a range of 20000. Set Y has a range of 50000. IF there is a set which contains both X and Y, What is the maximum and minimum range of the set comprising of both Set X and Set Y.
- by nikilnikil
Tue Nov 24, 2009 1:29 am- Forum: Problem Solving
- Topic: combined range of 2 Sets ?
- Replies: 7
- Views: 4587
4*10% + x*100% ______________ = 25% 4+x cross multiply, .4 + x = 1 + .25x .75x = .6 x = .6/.75 so, x = .8 Method is simple. First , use only percentage of water or percentage of solution throughout the solution. problem states: solution is 90% glycerin . I f there are 4 gallons of solution then how ...
- by nikilnikil
Mon Nov 23, 2009 1:22 pm- Forum: Problem Solving
- Topic: plz answer this mixture problem
- Replies: 8
- Views: 2823
you can alternatively solve this using the following method we can choose yellow, yellow, red yellow, red, yellow red, yellow, yellow so, 5/12 * 4/11 * 3/10 [ 5 out of 12 yellow, remaining 4 yellow out of 11, 3 red out of 10 ] + 5/12* 3/11 * 4/10 [ 5 out of 12 yellow, 3 red out of remaining 11 balls...
- by nikilnikil
Mon Nov 23, 2009 1:03 pm- Forum: Problem Solving
- Topic: Hii can anyone help me out in this please
- Replies: 2
- Views: 1270
- by nikilnikil
Fri Nov 20, 2009 10:43 am- Forum: Reading Comprehension
- Topic: 770 level - RC passage
- Replies: 8
- Views: 4508