question:In a certain animal population, for each of the first 3 months of life, the probability that an animal will die during that month is 1/10. For a group of 700 newborn members of the population, approximately how many would be expected to survive the first 3 months of life?
Options:
(A) 511
(B) 546
(C) 552
(D) 562
(E) 570
answer:(A)
Stream of consciousness:Number of newborns that can die in first month = 1/10 * 700 = 70
Survived = 630
Number of newborns that can die in second month = 1/10 * 630 = 63
Survived = 567
Number of newborns that can die in third month = 1/10 * 567 = 56
Survived = 511

question:The average age of A, B and C is 25 years. If the average age of A and C is 29 years, what is the age of B in years ?
Options:
(A) 17
(B) 35
(C) 20
(D) 32
(E) 21
answer:(A)
Stream of consciousness:Age of B = Age of (A + B + C) Age of (A + C) = 25 3 29 2 = 75 58 = 17 years

question:Find the simple interest on Rs.620 for 10 months at 10 paisa per month?
Options:
(A) 277
(B) 620
(C) 640
(D) 678
(E) 121
answer:
(B)
Stream of consciousness:I = (620*10*10)/100 = 620