Answer: (E)
Question: A technician makes a round-trip to and from a certain service center by the same route. If the technician completes the drive to the center and then completes 10 percent of the drive from the center, what percent of the round-trip has the technician completed?
Options:
(A) 5%
(B) 10%
(C) 25%
(D) 40%
(E) 55%
[CoT]: [Assuming that the technician makes a round-trip of 40 miles (each way is 20 miles), then the technician would have completed 20 miles + 2 miles (10% of the remaining 20 miles). Therefore, the total is 22 miles. 22miles/40 miles is 55% of the entire trip.]

Answer: (B)
Question: In 2005, 30 percent of the math department's 40 students were female, and in 2007, 40 percent of the math department's 65 students were female. What was the percent increase from 2005 to 2007 in the number of female students in the department?
Options:
(A) 15%
(B) 116%
(C) 136%
(D) 155%
(E) 160%
[CoT]: [Female students in 2005 = 30% of 40 = 12
Female students in 2007 = 40% of 65 = 26
Percentage increase = [(26 - 12)/12] *100 % = 116%]

Answer: (A)
Question: A train 360 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?
Options:
(A) 40 sec
(B) 42 sec
(C) 45 sec
(D) 48 sec
(E) 58 sec
[CoT]: [Speed = 45 * 5/18 = 25/2 m/sec
Total distance covered = 360 + 140 = 500 m
Required time = 500 * 2/25 = 40 sec]

Answer: (D)
Question:
The average of 20 numbers is zero. Of them, at the most, how many may be greater than zero?
Options:
(A) 22
(B) 28
(C) 29
(D) 20
(E) 21
[CoT]: [Average of 20 numbers = 0
Sum of 20 numbers = (0 * 20) = 0
It is quite possible that 19 of these numbers may be positive and if their sum is a, then 20th number is (-a).]