Rationale: One. You cannot have more mice if you start with one!
The answer: (A)
Question: Mice can multiply very fast. Adult mice can give birth once every month, and baby mice grow into adult mice in just two months after they are born. If you would buy a baby mouse just after it was born, how many mice would you have in 10 months?
Options:
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
Reasoning: 1 man's 1 day work = 1/100
(10 men + 15 women)'s 1 day work = 1/8
15 women's 1 day work = (1/8 - 10/100) = 1/40
1 woman's 1 day work = 1/600
1 woman alone can complete the work in 600 days.
Ans: (E)
Question: 10 men and 15 women together can complete a work in 8 days. It takes 100 days for one man alone to complete the same work. How many days will be required for one woman alone to complete the same work?
Options:
(A) 127 days
(B) 667 days
(C) 177 days
(D) 187 days
(E) 600 days
Rationale: Increase = (20/40)*100 = 50%.
The answer: (E)
Question: John makes $40 a week from his job. He earns a raise and now makes $60 a week. What is the % increase?
Options:
(A) 16%
(B) 16.66%
(C) 18%
(D) 21%
(E) 50%
Reasoning: Required time = (5 1/4)/3 + (5 1/4)/7 = 2 1/2 hours.
Ans: (A)
Question: A man walks at a speed of 3 km/hr and runs at a speed of 7 km/hr. How much time will the man require to cover a distance of 10 1/2 km, if he completes half of the distance, i.e., (5 1/4) km on foot and the other half by running?
Options:
(A) 2 1/2
(B) 2 1/6
(C) 4 1/2
(D) 2 1/1
(E) 2 1/8
Rationale: Speed of the boat in still water = (60+80)/2 = 70 kmph. Speed of the stream = (80-60)/2 = 10 kmph
The answer: (A)
Question: The speed of a boat in upstream is 60 kmph and the speed of the boat downstream is 80 kmph. Find the speed of the boat in still water and the speed of the stream?
Options:
(A) 70, 10 kmph
(B) 35, 27 kmph
(C) 50, 60 kmph
(D) 45, 55 kmph
(E) 45, 65 kmph
Rationale: P(1 + 20/100)n > 2P or (6/5)n > 2
Now, (6/5 * 6/5 * 6/5 * 6/5) > 2. So, n = 4 years.
The answer: (B)
Question: The least number of complete years in which a sum of money put out at 20% C.I. will be more than doubled is?
Options:
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7