The arithmetic mean of the sequence median of the

The Arithmetic mean of the sequence = Median of the sequence.
Therefore, A.M = 2n + 2
GRE QUANT DATABASE(UPDATED TILL December 10 th ) updated by Saranya
1) Given that, the probability that it won't rain tomorrow is 0.46
Col A: The probability that it will rain tomorrow at temperature of 85degree centigrade
Col B: 0.54
Solution :
p is the probability of success (probability that it will rain.)
q is the probability of failure (probability that it won't rain.)
then p + q = 1.
Given : q = 0.46
Therefore, p = 1 – 0.46 = 0.54
2) If 'N' is a 3 digit number where hundreds place is 'x' and units place is 'y' then what will be the
factor for N-100x-y?
A. 3 B. 4 C. 5 D. 6 E. 7
Solution :
Case 1 : Let us take N as 131, x = 1 and y = 1,
then , N-100x-y = 131 – 100-1= 30, which is a factor of 3, 5 and 6.
Case 2 : Let us take N as 456, x=4 and y = 6
then, N-100x-y = 456 – 400 – 6 = 50 , which is a factor of 5
Case 3 : Let us take N as 142, x=1and y = 2
then, N-100x-y = 142 – 100 – 2 = 40 , which is a factor of 4 and 5.
From all these cases, what we infer is, for any number of N, the factor for N-100x-y will be 5.
Answer is Option C (5)

3) If 'S' is a set of all integers that are multiples of 3 & multiples of 5, provided it should be of 2
digits, then find the range of S?
A. 81 B. 77 C. 87 D. 89 E. 91
Solution :
Multiples of 3 and Multiples of 5 ( condition : it should be of 2 digits)
Multiples of 3 = { 12 , 15 , 18 , 21 , ......................... , 99}
Multiples of 5 = { 10, 15, 20, 25, ............................. ,95}
Therefore, S = { 10,12,15,18, ........................... 99}
Range = Maximum number – Minimum Number
Range of S = 99 – 10 = 89
Answer : Option D (89)
4) Find the number of possible values of x & y in the expression (5+x)/(7+y), so that the resultant
ratio is 5:7 where x and y lie between 12 and 29?
Solution :
(5+x)/(7+y) = 5/7
x and y should lie between 12 and 29
To Find : x and y
5+x must be a multiple of 5 , the possible values will be (5+0), (5+5), (5+10), (5+15),(5+20),(5+25),
(5+30), ..................
7+y must be a multiple of 7 , the possible values will be (7+0), (7+7), (7+14), (7+21),(7+28),(7+35),
(7+42), ..................
(5+x)/(7+y) can be (5+0)/(7+0) , (5+5)/(7+7), (5+10)/(7+14), (5+15)/(7+21) , (5+20)/(7+28) , (5+25)/
(7+35) , (5+30)/(7+42)
All the above said are possible values that x and y can take, but
the condition given is x and y should lie between 12 and 29.
So , eliminating options, which does not lie in this range, we get
(5+15)/(7+21) and (5+20)/(7+28).
Answer : x = 15 and y = 21 (or) x = 20 and y = 28
Whichever option given in the question can be marked as the answer.
5) If -2 < x < -1, then
Col A: 1/x3
Col B: 1/x
Solution :

In all cases except x = -1 ,
the
value of 1/x3 > value of 1/x
Answer : Option A (Column A is greater)
Note : If the question given as If 2 < x < 1 , all positive values, then
In all cases except x = 1
Value of 1/x3 < value of 1/x.
GRE QUANT DATABASE(UPDATED TILL December 9
th
) updated by Saranya
1) A triangle ABC is given, in which lengths of two sides were given as BC = 12 , AC = 13 and the
perimeter of the triangle is 32.
Col A: Measure of angle of B
Col B: 90
Solution :
AB + BC + AC = 32
BC and AC are given as 12 and 13 , therefore, AB = 7
Note : Conditions to satisfy
If angle B to be Right
angle
Condition to be satisfied AB 2 + BC 2 = AC 2
If angle B to be an
Obtuse angle
Condition to be satisfied AB 2 + BC 2 < AC 2
If angle B to be an Acute
angle
Condition to be satisfied AB 2 + BC 2 > AC 2
In this question , if we solve the values we will get as AB 2 + BC 2 > AC 2
7
2
+ 12
2
> 13
2
, therefore, it is an acute angle
Answer : Option B ( Column B is greater )