Reasoning: Total age of students is 32X16 = 512 Years
Total age inclusive of teacher = 33X (16+1) = 561
So, Teacher's age is 561-512 = 49 Yrs
There is a shortcut for these type of problems
Teacher's age is 16+(33X1) = 49 Years
Ans: (C)
Question: The average age of a class of 32 students is 16 yrs. if the teacher's age is also included, the average increases by one year. Find the age of the teacher
Options:
(A) 45 Years
(B) 46 Years
(C) 49 Years
(D) 52 Years
(E) 54 Years
Rationale: If the last digit is 0, 2, 4, 6, or 8, the number is even and therefore not prime. If the last digit is 5, the number is divisible by 5 and therefore not prime. The only possibilities are 1, 3, 7, and 9. So the probability is approximately 1/4 (answer A). We say approximately because there is a certain degree of randomness in the distribution of prime numbers.
The answer: (A)
Question: A password for a computer is six digits from 0 and 9. The six digit number is a prime number. What is the approximate probability that the last digit is a 3?
Options:
(A) 1/4
(B) 1/6
(C) 1/10
(D) 1/20
(E) 1/50
Reasoning: Speed = 60*(5/18) m/sec = 50/3 m/sec
Length of Train (Distance) = Speed * Time
(50/3) * 9 = 150 meter
Ans: (A)
Question: A train running at the speed of 60 km/hr crosses a pole in 9 seconds. Find the length of the train.
Options:
(A) 150 m
(B) 145 m
(C) 140 m
(D) 135 m
(E) 155 m
Rationale: Assume the price = 100
Price during sale = 90
Price after sale = 100
Percent increase = 10/90*100 = 11% approx.
The answer: (C)
Question: During a sale, the price of a pair of shoes is marked down 10% from the regular price. After the sale ends, the price goes back to the original price. What is the percent of increase to the nearest percent from the sale price back to the regular price for the shoes?
Options:
(A) 9%
(B) 10%
(C) 11%
(D) 15%
(E) 90%
Reasoning: T = 192/32 = 6 h
T = 6 - 3 = 3
Time Ratio = 6:3 = 2:1
Speed Ratio = 1:2
Ans: (A)
Question: A motorcyclist goes from Bombay to Pune, a distance of 192 kms at an average of 32 kmph speed. Another man starts from Bombay by car 2 hours after the first, and reaches Pune hour earlier. What is the ratio of the speed of the motorcycle and the car?
Options:
(A) 1:2
(B) 1:8
(C) 1:1
(D) 1:6
(E) 1:3
Reasoning: ? = 9568 6548 1024 = 1996.
Ans: (B)
Question: What should come in place of the question mark (?) in the following equation?
9568 6548 1024 = ?
Options:
(A) 2086
(B) 1996
(C) 2293
(D) 1896
(E) None of these