Got it. Its purely combinations. I guess the direct probability method cannot be applied here.
Thats y i got confused, asking myself too many questions(if all the bulbs are unique, if 2 different orders shud be considered wen both are picked simultaneously). whew. Combinations seems alright.
Appreciate ur help!!
Why is there no activity on this thread?
:splat::splat::splat::splat::splat::splat::splat::splat:
Puys,
a long list of problems.. But the pain is I donthave the OA. I found these questions unanswered in earlier posts.
1.The sum of the first N-1 terms of an Arithmetic Progression is zero
or positve and sum of the first N terms is negative. What is the
value of N?
1. The common difference is -4 and the 7th term is the last positive term.
2. The first term is 25 and there are 7 positive terms and all are integers.
2. Is the five digited number ABCDE divisible by 13?
1. The number CD is divisible by 13.
2. 10A+B+4C+3D-E is divisible by 13.
3. The roots of a quadratic equatin ax^2+bx+c=0 are integers and
a+b+c>0 and a>0. Are both the roots of the equation positive?
(1) Sum of the roots is positive.
(2) Product of the roots is positive.
4. In triangle ABC angle A is the greatest angle. D is the foot of the
perpendicular dropped on to BC from A. Is triangle ABC
right-angled?
1. AD^2= BD x DC.
2. AD/DC
5. What is the reminder when X^4 + Y^4 is divided by 5
1. When X-Y is divided by 5 reminder is 1
2. When X+Y is divided by 5 reminder is 2
6.If x and y are positive integers such that x= 8y +12 ,what is the GCD of x and y?
a) x=12u , where u is an integer
b) y=12z , where z is an integer
My take on
Q5. Individual statements are suff to ans the q
Q6.Both statements are nt suff and additional info is needed to ans the q
My take on
Q5. Individual statements are suff to ans the q
Q6.Both statements are nt suff and additional info is needed to ans the q
Hi Deepakram,
It will be beneficial for everybody, if you will give detail logic behind it.
So that in this open forum everybody can discuss it!
Hoping to get detailed explanation !
cheers !
:cheers:
Solve this:
What is the proportion of women in Austria?
(I) Number of men in Austria is 5% more than the number of women
(II) Austria's population is 5% more than that of one of its neighboring countries, where women are 52% of the population.
Is x + y > 0 ?
(I) x - y > 1
(II) x/y + 1 > 0
A person bought an article at 15% discount and sold it for Rs 1600. What is the % profit?
(I) The marked price is 1500
(II) By selling the article at Rs 153 more, he would get 12% more
Is x + y > 0 ?
(I) x - y > 1
(II) x/y + 1 > 0
I would have marked option B..
(I) x - y > 1
(x+y)(x-y) > 1
(x+y) & (x-y) both should be either +ve or -ve..
NOT SUFF
(II) x/y + 1 > 0
solve eqn, (x+y)/y > 0
cross multiply, (x+y)>0
SUFF
Solve this:
What is the proportion of women in Austria?
(I) Number of men in Austria is 5% more than the number of women
(II) Austria's population is 5% more than that of one of its neighboring countries, where women are 52% of the population.
proportion of women in Austria = ratio of women in the population
Eqn1:
Number of men in Austria is 5% more than the number of women
Let men %age be X, and women be Y;
X = Y+5
X + Y + 5 = 100; X + Y = 95
Substitute values above and solve for Y and ratio can be found out.. (must be something like 47.5/52/5 or rather 47.5/100)
SUFF
Eqn2:
Austria's population is 5% more than that of one of its neighboring countries, where women are 52% of the population.
This does not help with the ratio of women in Australia...
NOT SUFF
I would have marked option A
plz share the OA.. 😉
A person bought an article at 15% discount and sold it for Rs 1600. What is the % profit?
(I) The marked price is 1500
(II) By selling the article at Rs 153 more, he would get 12% more
this looks like an incomplete question to me.. not sure if this is actual OG question since there is lot of ambigutiy around the terms used..
Marked Price: When he bought it or when he sold it
By selling the article at Rs 153 more: MORE than what..??.. CP, SP, MP..??..
i might be wrong in my comments above so maybe you would wanna wait for the pioneers of this thred to come and help u.. 😉
Is x + y > 0 ?
(I) x - y > 1
(II) x/y + 1 > 0
I would have marked option B..
(I) x - y > 1
(x+y)(x-y) > 1
(x+y) & (x-y) both should be either +ve or -ve..
NOT SUFF
(II) x/y + 1 > 0
solve eqn, (x+y)/y > 0
cross multiply, (x+y)>0
SUFF
Hey varun ...statement in bold is incorrect ...we cannot cross multiply to deduce the relation ...
I mean, its a ratio ..ratio is +ve when both den and numerator have the same polarity ...i.e both are +ve or both are -ve ..
We cannot rule out the poss of both x and y being -ve from St 2 ...
Even after combining, both could be +ve or -ve ...
Not suff ...
IMO ..Ans E
A person bought an article at 15% discount and sold it for Rs 1600. What is the % profit?
(I) The marked price is 1500
(II) By selling the article at Rs 153 more, he would get 12% more
this looks like an incomplete question to me.. not sure if this is actual OG question since there is lot of ambigutiy around the terms used..
Marked Price: When he bought it or when he sold it
By selling the article at Rs 153 more: MORE than what..??.. CP, SP, MP..??..
IMO Ans is D ..
Let original marked price be x
then, CP = 0.85x
SP =1600
% profit = *100
No need to calculate, if we have x, we have the value
St 1 : Marked price = x = 1500 ...enough info to solve.. suff
St 2 : new SP = 1753, old SP = 1600
hence, we can get the new and old profit % in terms of x
And the diff of these values is 12 ...Solving we have a definite value ..
Suff ...
Ans D ..OA please ?
IMO Ans is D ..
Let original marked price be x
then, CP = 0.85x
SP =1600
% profit = *100
No need to calculate, if we have x, we have the value
St 1 : Marked price = x = 1500 ...enough info to solve.. suff
St 2 : new SP = 1753, old SP = 1600
hence, we can get the new and old profit % in terms of x
And the diff of these values is 12 ...Solving we have a definite value ..
Suff ...
Ans D ..OA please ?
The solution seems to be OK.but one doubt-MP can be talken as CP?many times I have seen questions wherin MP is different from CP.
Is x + y > 0 ?
(I) x - y > 1
(II) x/y + 1 > 0
statement1.(x-y)(x+y)>1=>both expressions are either+ive or-Ive
+ive=>x>y
-ve=>x
statement2.
x/y>-1
x>-y
x+y>0
So 2 is suffecient.
The above approach fails when y is zero,in that case answer is E.But I believe dividing by zero is outside GMAt scope so will go for B
guy with guts SaysThe solution seems to be OK.but one doubt-MP can be talken as CP?many times I have seen questions wherin MP is different from CP.
MP may or may not be equal to CP ..
If retailer / wholesaler gives no discount, u buy at the marked price then CP = MP
But incase ,there is a discount, it is always calculated on MP, and hence CP is less than MP ...
In above sum as well, CP is not same as MP .
CP is 15 % less than MP or CP=0.85MP
statement1.(x-y)(x+y)>1=>both expressions are either+ive or-Ive
+ive=>x>y
-ve=>x
statement2.
x/y>-1
x>-y
x+y>0
So 2 is suffecient.
The above approach fails when y is zero,in that case answer is E.But I believe dividing by zero is outside GMAt scope so will go for B
well ...statement in bold is incorrect ..
If u multiply by y on both sides sign of inequality does not change only if y is positive ...OR in other words, u have already assumed y to be positive...incorrect assumption ...
It is not outside the scope of GMAT ...u have forgotten to calculate the other case i.e when x and y are both negative..
Ans E
Is x + y > 0 ?
(I) x - y > 1
(II) x/y + 1 > 0
1) (x-y)(x+y) > 1
LHS: both positive or both negative, NOT SUFF
2) (x+y)/y > 0
LHS: Nr and Dr can be both positive or both negative, NOT SUFF
Combine 1 and 2. NOT SUFF
Ans E?
Puys,
a long list of problems.. But the pain is I donthave the OA. I found these questions unanswered in earlier posts.
1.The sum of the first N-1 terms of an Arithmetic Progression is zero
or positve and sum of the first N terms is negative. What is the
value of N?
1. The common difference is -4 and the 7th term is the last positive term.
2. The first term is 25 and there are 7 positive terms and all are integers.
Good set of questions missed it earlier ...will try to attempt 1 at a time ..
Sum 1 : IMO Ans B
Explanation :
Sn-1>=0 and Sn
Now, Sn = n/2 ( T1 + Tn) OR Sn = n/2
St 1 : Now 8th term could be 0 or -ve Hence, T7 = 1,2,3 or 4
For sum to be -ve , there should be atleast as many -ve terms as many +ve terms , hence n has to be min of 14
however , we do not know T1 hence , we cannot fix the series ..
N could be 14, 15 or 16 ...not suff
St 2 : T1 = 25 and 7 postive terms only
Or in other words, 25 - 6d >=0 hence d =4
Hnce ,a fix series ...25,21,....1,-3 ....
Hnce n = 14
Suff ...
Ans B ..
Is x + y > 0 ?
(I) x - y > 1
(II) x/y + 1 > 0
IMO E.
My explanation
take 1) (x+y)(x-y) >1
this means (x+y) and (x-y) are both +ve or both -ve. so insuff to ans the question
take 2) x+y/y >0 this means x+y and y are both +ve or are both -ve.
so insuff to ans the ques
now take 1) and 2) still we donot get a definite answer.