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 900 kms and City A and City C is 300 kms. What is the ratio of their average speed of travel? (Eddy: Freddy)
Options:
(A) 8/3
(B) 3/8
(C) 8/5
(D) 4/1
(E) 5/3
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Distance traveled by Eddy = 900 km
Time taken by Eddy = 3 hours
Average speed of Eddy = 900/3 = 300 km/hour
Distance traveled by Freddy = 300 km
Time taken by Freddy = 4 hours
Average speed of Freddy = 300/4 = 75 km/hour
Ratio of average speed of Eddy to Freddy = 300/75 = 4/1 So the answer is: (D).
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A train 350 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 18 sec
(B) 20 sec
(C) 76 sec
(D) 15 sec
(E) 17 sec
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Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 350 * 2/35 = 20 sec So the answer is: (B).
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If 85 percent of the test takers taking an old paper and pencil GMAT exam answered the first question on a given math section correctly, and 70 percent of the test takers answered the second question correctly, and 5 percent of the test takers answered neither question correctly, what percent answered both correctly?
Options:
(A) 60 %
(B) 65 %
(C) 70%
(D) 75%
(E) 80%
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{Total} = {First correctly} + {Second correctly} - {Both correctly} + {Neither correctly}
100 = 85 + 70 - {Both correctly} + 5
{Both correctly} = 60. So the answer is: (A).
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