(Ans). (E)
(Question). Eddy and Freddy start simultaneously from city A and they travel to City B and City C respectively. Eddy takes 3 hours and Freddy takes 4 hours to complete the journey. If the distance between City A and City B is 600 kms and City A and City C is 360 kms. What is the ratio of their average speed of travel? (Eddy: Freddy)
Options:
(A) 8/3
(B) 3/8
(C) 8/5
(D) 5/8
(E) 20/9
(CoT). Distance traveled by Eddy = 600 km
Time taken by Eddy = 3 hours
Average speed of Eddy = 600/3 = 200 km/hour
Distance traveled by Freddy = 360 km
Time taken by Freddy = 4 hours
Average speed of Freddy = 360/4 = 90 km/hour
Ratio of average speed of Eddy to Freddy = 200/90 = 20/9


(Ans). (A)
(Question). If x, y, and z are positive integers such that x is a factor of y and y is a factor of z, which of the following is NOT necessarily an integer?
Options:
(A) (x + y) /z
(B) (y + z) /x
(C) yz/x
(D) (2y + 3z) /x
(E) (xy + z) /y
(CoT). As per the question, let x = 2, y = 6, and z = 12. Plugging these into the answer choices, only A does not yield an integer.


(Ans). (A)
(Question). In a certain animal population, for each of the first 3 months of life, the probability that an animal will die during that month is 1/10. For a group of 700 newborn members of the population, approximately how many would be expected to survive the first 3 months of life?
Options:
(A) 511
(B) 546
(C) 552
(D) 562
(E) 570
(CoT). Number of newborns that can die in first month = 1/10 * 700 = 70
Survived = 630
Number of newborns that can die in second month = 1/10 * 630 = 63
Survived = 567
Number of newborns that can die in third month = 1/10 * 567 = 56
Survived = 511


(Ans). (C)
(Question).

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Look at this series: 53, 53, 40, 40, 27, 27, ... What number should come next?
Options:
(A) 12
(B) 15
(C) 14
(D) 18
(E) 17
(CoT). In this series, each number is repeated, then 13 is subtracted to arrive at the next number.