q: The average of Suresh's marks in English and History is 55. His average of marks in English and Science is 65. What is the difference between the marks which he obtained in History and Science?
Options:
(A) 40
(B) 60
(C) 20
(D) Data inadequate
(E) None of the above
a: Stream of consciousness: E + H = (55 2) = 110;
E + S = (65 2) = 130
Reqd difference = 130 110 = 20 The answer is (C).
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q: In how many different ways can the letters of the word JUDGE be arranged so that the vowels always come together?
Options:
(A) 48
(B) 24
(C) 120
(D) 60
(E) None of these
a: Stream of consciousness: Reqd. number = 4! 2! = 24 2 = 48 The answer is (A).
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q: Two trains are traveling on parallel tracks in the same direction. The faster train travels at 130 miles per hour, while the slower train travels at 80 miles per hour. At 2 o'clock the faster train is 20 miles behind the slower one. How far apart are the two trains at 5 o'clock?
Options:
(A) 60 miles
(B) 80 miles
(C) 90 miles
(D) 130 miles
(E) 400 miles
a:
Stream of consciousness: Answer = D. 130 miles
Relational speed = 130 - 80 = 50 miles per hour
In 3 hours, difference = 50 * 3 = 150 miles
Fast train trailing 20 miles, so effective difference = 150 - 20 = 130 miles The answer is (D).
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