Rationale: Work done by all three of them in one day = 1/4 + 1/8 + 1/12 = 11/24
The number of days required = 24/11 = 2 2/11 days.
The answer: (E)
Question: A, B and C can do a work in 4 days, 8 days and 12 days respectively. In how many days can all three of them working together, complete the work?
Options:
(A) 2 2/3
(B) 2 2/8
(C) 2 2/0
(D) 2 2/2
(E) 2 2/11
Reasoning: 1 yard = 36 Inch
4 yard = 36*4 = 144 inch
15 inch req. for 1 bow
Max. no. of bows possible = 144/15 = 9 bows and 9 inch ribbon left.
Ans: (A)
Question: a piece of ribbon 4 yard long is used to make bows requiring 15 inches of ribbon for each.What is the maximum number of bows that can be made.
Options:
(A) 9
(B) 8
(C) 7
(D) 6
(E) 5
Rationale: D = 100 + 250 = 350
S = 36 * 5/18 = 10 mps
T = 350/10 = 35 sec
The answer: (B)
Question: How many seconds will a train 100 meters long take to cross a bridge 250 meters long if the speed of the train is 36 kmph?
Options:
(A) 54 sec
(B) 35 sec
(C) 25 sec
(D) 45 sec
(E) 24 sec
Reasoning: 12400 + 6899 = 610+ ?
12400 + 6899 610 = 18689
Ans: (C)
Question: What should come in place of the question mark (?) in the following equation?
12400 + 6899 = 610+ ?
Options:
(A) 12345
(B) 56894
(C) 18689
(D) 23478
(E) 94561
Rationale: 70 + 50 = 120 * 5/18 = 100/3 mps
D = 150 + 100 = 250 m
T = 250 * 3/100 = 15/2 = 7 1/2 sec
The answer: (D)
Question: Two trains are moving at 50 kmph and 70 kmph in opposite directions. Their lengths are 150 m and 100 m respectively. The time they will take to pass each other completely is?
Options:
(A) 7 1/9
(B) 7 1/8
(C) 7 1/3
(D) 7 1/2
(E) 7 1/1
Rationale: Required time = (6)/3 + (6)/6 = 3 hours.
The answer: (E)
Question: A man walks at a speed of 3 km/hr and runs at a speed of 6 km/hr. How much time will the man require to cover a distance of 12 km, if he completes half of the distance, i.e., (6) km on foot and the other half by running?
Options:
(A) 2.6
(B) 2.2
(C) 2.5
(D) 2
(E) 3