Find the wrong number below mentioned series
3,20,50,60,80
Options:
(A) 80
(B) 60
(C) 50
(D) 20
(E) 3

3 is the only prime number or odd number in the series. So the answer is: (E).

What will come in place of the x in the following Number series? 2, 7, 27, 107, 427, x
Options:
(A) 1427
(B) 1607
(C) 1707
(D) 2047
(E) 2147

2
2 × 4 - 1 = 7
7 × 4 - 1 = 27
27 × 4 - 1 = 107
107 × 4 - 1 = 427
427 × 4 - 1 = 1707 So the answer is: (C).

If in a certain sequence of consecutive multiples of 100, the median is 650, and the greatest term is 1000, how many terms that are smaller than 650 are there in the sequence?
Options:
(A) 6
(B) 4
(C) 8
(D) 12
(E) 13

Since the median is 650 we know there must be a even number of integers
So the list around 625 must go. 600 ( 650) 700 800 900 1000
Since we know there are 4 numbers greater than 650 then there must be 4 numbers less then 650. So the answer is: (B).

Three people took GMAT practice tests in which the minimum and maximum possible scores are 200 and 800, respectively. They each took a test 3 times, and no one scored below 510 or over 780. If the individual ranges of the three people's scores in those 3 practice tests were 20, 90 and 130, what is the difference between the maximum and minimum possible ranges of all their scores put together.
Options:
(A) 70
(B) 80
(C) 90
(D) 140
(E) 170


According to the information in the question the maximum range would be between 510 and 780(270). The minimum range would be the greatest range for any one individual, which is listed in the problem as 130. So the difference between these would be 270-130 or 140. So the answer is: (D).