Q1. The average weight of 16 boys in a class is 50.25 kg and that of the remaining 8 boys is 45.15 kg. Find the average weights of all the boys in the class.

A. 47.55 kg B. 48 kg C. 48.55 kg D. 49.25 kg

Answer: C
Explanation: Required Average = [latex](\frac {50.25 \times 16 + 45.15 \times 8}{16 + 8})[/latex]
= [latex]\frac {804 + 361.20}{24}[/latex]
= [latex]\frac {1165.20}{24}[/latex]
= 48.55
Q2. A library has an average of 510 visitors on Sundays and 240 on other days. The average number of visitors per day in a month of 30 days beginning with a Sunday is:

A. 250 B. 276 C. 280 D. 285

Answer: D
Explanation: Required Average = [latex](\frac {510 \times 5 + 240 \times 5}{30})[/latex]
= [latex]\frac {8550}{30}[/latex]
= 285
Q3. If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55, 60, then the average marks of all the students is:

A. 53.33 B. 54.68 C. 55 D. None of these

Answer: B
Explanation: Required Average = [latex](\frac {55 \times 50 + 60 \times 55 + 45 \times 60}{55 + 60 + 45})[/latex]
= [latex]\frac {2750 + 3300 + 2700}{160}[/latex]
= [latex]\frac {8750}{160}[/latex]
= 54.68
Q4. A pupil's marks were wrongly entered as 83 instead of 63. Due to that the average marks for the class got increased by half (1/2). The number of pupils in the class is:

A. 10 B. 20 C. 40 D. 73

Answer: C
Explanation: Let there be x pupils in the class.
Total increase in marks = [latex](x \times \frac {1}{2}) = \frac {x}{2}[/latex]
therefore, [latex] \frac {x}{2} = (83 - 63) \Rightarrow \frac {x}{2}[/latex] = 20
[latex]\Rightarrow x = 40[/latex]
Q5. The average monthly income of P and Q is Dollar 5050. The average monthly income of Q and R is Dollar 6250 and the average monthly income of P and R is Dollar 5200. The monthly income of P is:

A. Dollar 3500 B. Dollar 4000 C. Dollar 4050 D. Dollar 5000

Answer: B
Explanation: Let P, Q and R represent their respective monthly incomes. Then, we have:
P + Q = [latex](5050 \times 2) [/latex] = 10100 .... (i)
Q + R = [latex](6250 \times 2) [/latex] = 12500 .... (ii)
P + R = [latex](5200 \times 2) [/latex] = 10400 .... (iii)
Adding (i), (ii) and (iii), we get: 2 (P + Q + R) = 33000 or P + Q + R = 16500 .... (iv)
Subtracting (ii) from (iv), we get P = 4000. P's monthly income = Dollar 4000.

Q1. Look at this series: 1.5, 2.3, 3.1, 3.9, ... What number should come next?

A. 4.2 B. 4.4 C. 4.7 D. 5.1

Answer: C
Explanation: In this simple addition series, each number increases by 0.8.
Q2. Look at this series: 14, 28, 20, 40, 32, 64, ... What number should come next?

A. 52 B. 56 C. 96 D. 128

Answer: B
Explanation: This is an alternating multiplication and subtracting series: First, multiply by 2 and then subtract 8.
Q3. Look at this series: 2, 4, 6, 8, 10, ... What number should come next?

A. 11 B. 12 C. 13 D. 14

Answer: B
Explanation: This is a simple addition series. Each number increases by 2.
Q4. Look at this series: 201, 202, 204, 207, ... What number should come next?

A. 205 B. 208 C. 210 D. 211

Answer: D
Explanation: In this addition series, 1 is added to the first number; 2 is added to the second number; 3 is added to the third number; 4 is added to the fourth number; and go on.
Q5. Look at this series: 544, 509, 474, 439, ... What number should come next?

A. 404 B. 414 C. 420 D. 445

Answer: A
Explanation: This is a simple subtraction series. Each number is 35 less than the previous number.

Directions: The below questions are meant to test your knowledge of percentages. Percentages are fractions of 100 so for example 40 out of 100 is 40/100=0.4 which again is 40%.
Q1. Two students appeared at an examination. One of them secured 9 marks more than the other and his marks were 56% of the sum of their marks. The marks obtained by them are:

A. 39, 30 B. 41, 32 C. 42, 33 D. 43, 34

Answer: C
Explanation: Let their marks be [latex](x + 9) and x[/latex]
Then, [latex] x + 9 = \frac {56}{100(x + 9 + x)}[/latex]
25 [latex](x + 9) = 14 (2 x + 9)[/latex]
[latex]3 x = 99[/latex]
[latex] x = 3[/latex]
So, their marks are 42 and 33
Q2. A fruit seller had some apples. He sells 40% apples and still has 420 apples. Originally, he had:

A. 588 apples B. 600 apples C. 672 apples D. 700 apples

Answer: D
Explanation: Suppose originally he had x apples.
Then, (100 - 40)% of x = 420.
[latex]\frac {60}{100} \times x = 420 [/latex]
[latex]x = \frac {(420 \times 100)}{60 }= 700 [/latex]
Q3. What percentage of numbers from 1 to 70 have 1 or 9 in the unit's digit?

A. 1 B. 14 C. 20 D. 21

Answer: C
Explanation: Clearly, the numbers which have 1 or 9 in the unit's digit, have squares that end in the digit 1.
Such numbers from 1 to 70 are 1, 9, 11, 19, 21, 29, 31, 39, 41, 49, 51, 59, 61, 69.
Number of such number =14
Required percentage = [latex](\frac {14}{70} \times 100) % = 20 %[/latex]
Q4. If A = x% of y and B = y% of x, then which of the following is true?

A. A is smaller than B. B. A is greater than B C. Relationship between A and B cannot be determined. D. None of these

Answer: D
Explanation: [latex] x % of y [/latex]= [latex]( \frac {x}{100} \times y) [/latex] = [latex](\frac {y}{100} \times x) = y % of x [/latex]
A = B.
Q5. In a certain school, 20% of students are below 8 years of age. The number of students above 8 years of age is 2/3 of the number of students of 8 years of age which is 48. What is the total number of students in the school?

A. 72 B. 80 C. 120 D. 100

Answer: D
Explanation: Let the number of students be x.
Then, Number of students above 8 years of age = (100 - 20) % of x = 80 % of x.
80 % of x = 48 + [latex]\frac {2}{3} [/latex]of 48
[latex]\frac {80}{100} x[/latex] = 80
x = 100.