Rationale: Present age of 5 members = 5 x 17 + 3 x 5 = 100 years
Also, present ages of 5 members + Age of the baby = 6 x 17 = 102 years
Age of the baby = 102 100 = 2 years.
The answer: (B)
Question: Three years ago, the average age of a family of 5 members was 17. A baby having been born, the average age of the family is the same today. What is the age of the child?
Options:
(A) 3
(B) 2
(C) 4
(D) 1
(E) 5
Reasoning: Let the distance covered by the taxi be 'x' km. Then, distance covered by bus = (60 x) km. 20x + 10 (60 x)20x + 600 10x = 800 10x = 200 x = 20 km. He traveled 20 km by taxi.
Ans: (E)
Question: If man pays 20 for each km which he travels by taxi
and 10 for each km which he travels by bus. If in one
week he payed 800 for traveling 60 km. How many kilometers did he travel by taxi ?
Options:
(A) 23
(B) 78
(C) 27
(D) 29
(E) 20
Rationale: 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
The answer: (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) 34 Years
(B) 37 Years
(C) 49 Years
(D) 51 Years
(E) 57 Years
Reasoning: 30000(11/10)4 - 30000(6/5)2 = 723
Ans: (E)
Question: How much more would Rs.30000 fetch, after two years, if it is put at 20% p.a. compound interest payable half yearly than if is put at 20% p.a. compound interest payable yearly?
Options:
(A) 482
(B) 725
(C) 992
(D) 837
(E) 723
Rationale: 25 + 15 + 55 = 95% 100 - 95 = 5% to all others
The answer: (D)
Question: If a company allocates 25 percent of its budget to advertising, 15 percent to capital improvements, and 55 percent to salaries, what fraction of its budget remains for other allocations?
Options:
(A) 4/5
(B) 3/5
(C) 3/10
(D) 1/20
(E) 1/40
Rationale: Using the elimination method the option that fits this description is 26
6-2 = 4 (unit's digit that exceeds its ten's digit by 3)
26*8 = 208 (the product of the given number and the sum of its digits is equal to 175)
The answer: (D)
Question: Which of the options is a two-digit number, which has a unit's digit that exceeds its ten's digit by 4 and the product of the given number and the sum of its digits is equal to 208.
Options:
(A) 15
(B) 37
(C) 55
(D) 26
(E) 73