IMO Ans C ..
We need to check if x+z=2y i.e is y avg of x and z ?
St 1 : implies avg of x,y,z is lesser than 4. OR in other words, x+y+zeg If x,y,z is 1,2,3 resp then Avg(1,2,3,4) > Avg(1,2,3) and y is avg of x and z
If x,y,z is 0,2,3 resp then avg(0,2,3,4)>Avg(0,2,3) but y is not avg of x and z ...
Not suff
St 2 : Implies y>4 ...
Again not suff, since y need not necessarily be avg of x and z ...
Not suff ...
Combined : x+y+z4 ....
if y is avg of x and z then x+y+z would be 3y and if y>4 then total would exceed 12 ...So y can never be avg of x and z ...
-----------------------------------------------------------------------St 2: I don't think st 2 implies that y > 4.
If the probability that Mike can win a championship is 1/4, and that of Rob winning is 1/3 and that of Ben winning is 1/6, what is the probability that Mike or Rob win the championship but not Ben?
My solution = 1/4+1/3 - 1/6 = 5/12
(Some ppl are arguing that it shud be only 1/4 + 1/3 = 7/12 with the following argument which I do not trust)
In this situation we are dealing with mutually exclusing events - there is only one person who wins the championship. If Mike or Rob win the championship it automatically means that Ben doesn't win the championship. The answer should be 1/4+1/3 = 7/12.)
In the fig below, equilateral triangle ABC is inscribed in the circle. If the length of arc ABC is 24, what is the approximate diameter of the circle.
dude, where's the figure?
sumitg04 SaysIn the fig below, equilateral triangle ABC is inscribed in the circle. If the length of arc ABC is 24, what is the approximate diameter of the circle.
Ok.. I m back!!!
Length of major arc = 24
Due to symmetry, length of minor arc = 24/2 => 12
So, Circumference = 24+12 => 36 = 2(3.14)r
SO, r ~ 6
dia,d = 12 shd. be d answer...
sumitg04 SaysIn the fig below, equilateral triangle ABC is inscribed in the circle. If the length of arc ABC is 24, what is the approximate diameter of the circle.
Sorry....Didn't know how to draw a figure here....
what is the greatest possible area of a triangular region with one vertex at the center of a circle of radius 1 and the other two vertices on the circle?
what is the greatest possible area of a triangular region with one vertex at the center of a circle of radius 1 and the other two vertices on the circle?
Nitin Das Sayswhat is the greatest possible area of a triangular region with one vertex at the center of a circle of radius 1 and the other two vertices on the circle?
in this case we will get an isoceles triangle as 2 sides will be equal in length [ same as radius] and isoceles triangle with maximum area is formed when it is right angled [here right angle will be formed at center of circle].
SO area will be 1/2 * r*r = 1/2 * 1* 1 = 0.5
How many different ways can 3 cubes be painted if each cube is painted one color and only the 3 colors red, blue and green are available?( Order is not considered , for example , green,green, blue is considered the same as green, blue, green.)
Please post the explanation. Thanks In advance.
hi all,
Can anyone tell me the split up of questions topic wise so that i can spend more time on topics from which more questions are likely 2 come.
Thanks in advance.
hi all,
Can anyone tell me the split up of questions topic wise so that i can spend more time on topics from which more questions are likely 2 come.
Thanks in advance.
Hi,
The topics covered in Gmat Math are:
- Algebra (integers,prime nos, odd/even, divisiblity rules, factors and multiples)
- Arithmetic (arithmetic operations, percentages, fractions, ratio, decimals, avergaes, exponents and radicals, factorization, rate*time problems, work problems, function problems)
- Geometry (degrees and angles, triangles, circles, rectangles, squares, and other four-sided objects, solids and volume, coordinate geometry)
- Probablility, Permuation and Combination and Statistics(mean,mode,median,range and standard deviation).
But no body can tell you what the break-up of individual topics cause the computer gives you question based on your ability of ques getting right or wrong, so it's the computer chooses the break-up of your questions then and there in the paper.
so ple don't go on predicting that you'll only get ques from algebra, arithmetic, geometry and not from prob and stats or vice-versa.
Regards,
Neha
Thank you so much Neha...will it suffice if i cover kaplan 800 book or anything else is needed?
mathenthu SaysThank you so much Neha...will it suffice if i cover kaplan 800 book or anything else is needed?
I don't know how is Kaplan 800, cause i haven't used it.
I used Princeton which covers the basic of all chapters.
and then OG-10,11,12.
If you ask me, then these books are sufficient.
Apart from these i don't think any other book is required. you can still ask other people also if you want much better opinion on this.don't solely depend on my choice. ask other people too that's what i'll sugggest.
All the Best.
Regards,
Neha
hi,
Please help me with these:
1) In an examination, the max marks for each of 3 papers is 50 each. The max marks for the fourth paper is 100. Find the no of ways with which a student can score 60% marks in aggregate.
Ans is : 110551.
2) A new flag is to be designed with 6 vertical stripes using some of or all of the colors yellow, blue, green and red. The no of ways this can be done so that no 2 adjacent stripes have the same color?
a) 12*27 b) 12*81 c) 16*36 d) 16*27
3) The no of ways of factorizing 91000 into 2 factors, m and n such that m>1 , n>1 and gcd(m,n)=1 is
a) 15 b) 7 c) 32 d) none.
2) A new flag is to be designed with 6 vertical stripes using some of or all of the colors yellow, blue, green and red. The no of ways this can be done so that no 2 adjacent stripes have the same color?
a) 12*27 b) 12*81 c) 16*36 d) 16*27
@Mathentu
I was able to slove this...i think its the simplest among the 3
6 stripes of flag so the combinations of color wud be
4-3-3-3-3-3 i.e....4x3x3x3x3x3 = 12 x 81
Ans - B
2) A new flag is to be designed with 6 vertical stripes using some of or all of the colors yellow, blue, green and red. The no of ways this can be done so that no 2 adjacent stripes have the same color?
a) 12*27 b) 12*81 c) 16*36 d) 16*27
@Mathentu
I was able to slove this...i think its the simplest among the 3
6 stripes of flag so the combinations of color wud be
4-3-3-3-3-3 i.e....4x3x3x3x3x3 = 12 x 81
Ans - B
hi,
i think u arrived at the above answer this way:
1) first stripe can be filled in 4 ways, second in 3 ways , 3rd in 3 ways etc
but what if second and third or any other position is filled wth same color? Where is the condition that adjacent stripes should not be of same color beng addressed here? Please clarify
How many different ways can 3 cubes be painted if each cube is painted one color and only the 3 colors red, blue and green are available?( Order is not considered , for example , green,green, blue is considered the same as green, blue, green.)
Please post the explanation. Thanks In advance.
I think the ans for this should be 3^3 ie each cube can be painted in 3 colors. What is the OA ?
hi,
Please help me with these:
3) The no of ways of factorizing 91000 into 2 factors, m and n such that m>1 , n>1 and gcd(m,n)=1 is
a) 15 b) 7 c) 32 d) none.
Posting after a long time !!
IMO Ans is B ..
91000 = 2^3*5^3*7*13 ...we need to choose a pair of co prime nos greater than 1 ..
wee need to form 2 grps of nos from a set of 4 prime factors
Grps can be formed as :
a) 1 set and other 3 sets - 4 ways
b) 2 set and other 2 set - 3 ways
Hence...total is 7 ways ..Ans B ..
Will attempt first question tomm ...i know the concept fr the first one...have forgotten the formula ..
2) A new flag is to be designed with 6 vertical stripes using some of or all of the colors yellow, blue, green and red. The no of ways this can be done so that no 2 adjacent stripes have the same color?
a) 12*27 b) 12*81 c) 16*36 d) 16*27
@Mathentu
I was able to slove this...i think its the simplest among the 3
6 stripes of flag so the combinations of color wud be
4-3-3-3-3-3 i.e....4x3x3x3x3x3 = 12 x 81
Ans - B
hi,
i think u arrived at the above answer this way:
1) first stripe can be filled in 4 ways, second in 3 ways , 3rd in 3 ways etc
but what if second and third or any other position is filled wth same color? Where is the condition that adjacent stripes should not be of same color beng addressed here? Please clarify
Hey mathentu, missiongmat is correct ...
for the first stripe ...u have 4 options ..
for the next one ..all colors except the first ...hence 3 options..
for 3rd stripe...any color except the one used for 2nd stripe ...hence again 3 options ...
Likewise for other stripes as well ..hence adjacent repetition has been taken care of ..
Ans ..4*3^5 or 12*81...