question: How many liters of oil at Rs.40 per liter should be mixed with 240 liters of a second variety of oil at Rs.60 per liter so as to get a mixture whose cost is Rs.52 per liter?
Options:
(A) 120
(B) 150
(C) 160
(D) 180
(E) 200
answer: Stream of consciousness: 8:12 = 2:3
If 240 lrs of the 2nd variety taken then the 1st variety should be taken as 160 lr The answer is (C).


q: Two trains are traveling on parallel tracks in the same direction. The faster train travels at 110 miles per hour, while the slower train travels at 100 miles per hour. At 1 o’clock the faster train is 40 miles behind the slower one. How far apart are the two trains at 7 o'clock?
Options:
(A) 20 miles
(B) 80 miles
(C) 90 miles
(D) 120 miles
(E) 400 miles
a: Stream of consciousness: Answer = A. 20 miles
Relational speed = 110 - 100 = 10 miles per hour
In 6 hours, difference = 10 * 6 = 60 miles
Fast train trailing 40 miles, so effective difference = 60 - 40 = 20 miles The answer is (A).


question: Sarah's seafood restaurant gets a delivery of fresh seafood every day, 6 days per week, and her delivery company charges her dollars per delivery plus cents per item delivered. If lst week Sarah's seafood restaurant had an average of x items per day delivered, then which of the following is the total cost, in dollars, of last week's deliveries ?
Options:
(A) 6cdx/100
(B) d + 6cx/100
(C) 6d + xc/100
(D) 6d + 6xc/100
(E) 6cdx
answer: Stream of consciousness: Answer will be D. Straightforward question. The answer is (D).


q: If C is the temperature in degrees Celsins and F is the temperature in degrees Fahrenheit, then the relationship between temperatures on the two scales is expressed by the equation 9C=5(F-32). The temperature to boil water at sea level altitude and to boil on top of Mt. Everest differed by 15 degrees on the Fahrenheit scale, by how many degrees did the temperature extremes differ on the Celsius scale?
Options:
(A) a)  65/9
(B) b) 7
(C) c)  25
(D) d)  45
(E) e)  81
a: Stream of consciousness: The relationship is 9/5 - 32, so approximately half of difference in Celsius (the -32 part won't be used in this case). Just looking at the answer choices you can pick B which is the only number near half of 15. The other answer choices are too far apart so no need to calculate. The answer is (B).


question: What is the smallest positive integer x, such that 1,152x is a perfect cube?
Options:
(A) 4
(B) 6
(C) 8
(D) 12
(E) 18
answer: Stream of consciousness: We need to make 1152x a perfect cube, hence we need to have the powers a multiple of 3
1152 = 2^7*3^2
The minimum value of x for which 1152x is a perfect cube = 2^2*3 = 12 The answer is (D).


question: Express a speed of 720 kmph in meters per second?
Options:
(A) 120 mps
(B) 200 mps
(C) 181 mps
(D) 190 mps
(E) 125 mps
answer:

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
Stream of consciousness: 720 * 5/18 = 200 mps The answer is (B).