About this quiz
Tables, charts, data sufficiency, number matrix and calendar.
This Lok Sewa practice set has 50 multiple-choice questions (Subject: Mental Ability · For: Nayab Subba, Kharidar, Section Officer · Level: Medium). Take the quiz above first; after that, use the study list below to revise every question with its correct answer and a short explanation.
Study list: all 50 questions with answers and explanations
In a pie chart, the whole circle represents:
- A) 360° = 100% ✔
- B) 180° = 100%
- C) 100° = 100%
- D) 90° = 100%
Why: The whole circle is 360° and stands for the total, i.e. 100%. Each sector's angle is its share of 360°.
In a pie chart, 1% equals:
- A) 3.6° ✔
- B) 1°
- C) 36°
- D) 0.36°
Why: 360° ÷ 100 = 3.6°, so each 1% of the data takes 3.6° of the circle.
A sector of 90° in a pie chart represents:
- A) 25% ✔
- B) 90%
- C) 50%
- D) 10%
Why: Percentage = angle ÷ 3.6 = 90 ÷ 3.6 = 25%. 90° is a quarter of the circle, so it is a quarter of the total.
A sector of 72° represents:
- A) 20% ✔
- B) 72%
- C) 25%
- D) 15%
Why: 72 ÷ 3.6 = 20%. Or 72/360 = 1/5 = 20%.
If education gets 30% of a Rs 2,00,000 budget, it gets:
- A) Rs 60,000 ✔
- B) Rs 30,000
- C) Rs 6,000
- D) Rs 1,40,000
Why: 30% of 2,00,000 = 2,00,000 × 30 ÷ 100 = Rs 60,000.
In a pie chart, 15% is shown by how many degrees?
- A) 54° ✔
- B) 15°
- C) 45°
- D) 60°
Why: Angle = percentage × 3.6 = 15 × 3.6 = 54°.
Sales rose from 120 to 150 units. The percentage increase is:
- A) 25% ✔
- B) 30%
- C) 20%
- D) 15%
Why: Increase = 150 − 120 = 30. % increase = 30 ÷ 120 × 100 = 25%. Always divide by the old (starting) value.
Sales rose from 150 to 180 units. The percentage increase is:
- A) 20% ✔
- B) 30%
- C) 25%
- D) 18%
Why: Increase = 30, but now the old value is 150: 30 ÷ 150 × 100 = 20%. The same increase gives a smaller % on a bigger base.
The average of 120, 150 and 180 is:
- A) 150 ✔
- B) 140
- C) 160
- D) 450
Why: Average = sum ÷ count = (120 + 150 + 180) ÷ 3 = 450 ÷ 3 = 150.
A value fell from 200 to 150. The percentage decrease is:
- A) 25% ✔
- B) 50%
- C) 33.3%
- D) 20%
Why: Decrease = 200 − 150 = 50. % decrease = 50 ÷ 200 × 100 = 25%.
Two bars show 40 and 60. Their ratio is:
- A) 2 : 3 ✔
- B) 3 : 2
- C) 4 : 5
- D) 1 : 2
Why: 40 : 60. Divide both by their HCF, 20: 2 : 3.
If 40 out of 200 students failed, the pass percentage is:
- A) 80% ✔
- B) 20%
- C) 40%
- D) 60%
Why: Passed = 200 − 40 = 160. Pass % = 160 ÷ 200 × 100 = 80%. (Fail % = 20%.)
Total of a table column is 500 and one item is 125. Its share is:
- A) 25% ✔
- B) 12.5%
- C) 50%
- D) 20%
Why: Share = 125 ÷ 500 × 100 = 25%.
In data sufficiency, you need to decide:
- A) Whether the given data is enough to answer ✔
- B) The exact final answer always
- C) The longest statement
- D) Which statement is true in real life
Why: In data sufficiency you don't need the final answer. You only decide whether statement I, II, either, or both together give enough data to answer.
What is Ram's age? I: Ram is 5 years older than Shyam. II: Shyam is 20. The answer is:
- A) Both together are needed ✔
- B) I alone is sufficient
- C) II alone is sufficient
- D) Neither is sufficient
Why: I alone gives only the difference, and II alone gives only Shyam's age. Together: Ram = 20 + 5 = 25, so both are needed.
What is the area of a square? I: Side is 5 cm. II: Diagonal is 5√2 cm. The answer is:
- A) Either I or II alone is sufficient ✔
- B) Only I is sufficient
- C) Only II is sufficient
- D) Both together are needed
Why: I gives side 5 cm, so area = 25 cm². II gives diagonal 5√2, and side = diagonal ÷ √2 = 5, so area = 25 cm². Either alone is enough.
Is a number divisible by 6? I: It is divisible by 2. II: It is divisible by 3. The answer is:
- A) Both together are needed ✔
- B) I alone is sufficient
- C) II alone is sufficient
- D) Neither is sufficient
Why: 6 = 2 × 3. Knowing only one of the two facts is not enough, but divisible by both 2 and 3 means divisible by 6. Both are needed.
What is the price of one pen? I: 2 pens cost Rs 40. II: A pen costs Rs 5 more than a pencil. The answer is:
- A) I alone is sufficient ✔
- B) II alone is sufficient
- C) Either alone
- D) Both together are needed
Why: I alone: 2 pens cost Rs 40, so 1 pen = Rs 20. II only compares with a pencil whose price is unknown, so it is not enough. I alone is sufficient.
How many students are in a class? I: There are 20 boys. II: Girls are 25% more than boys. The answer is:
- A) Both together are needed ✔
- B) I alone
- C) II alone
- D) Neither
Why: I gives only boys. II gives only a relation. Together: girls = 20 + 25% of 20 = 25, total = 20 + 25 = 45. Both are needed.
What is x? I: x + y = 10. II: x − y = 4. The answer is:
- A) Both together are needed ✔
- B) I alone
- C) II alone
- D) Neither
Why: One equation with two unknowns can't be solved. Together: adding them gives 2x = 14, so x = 7. Both are needed.
What day is today? I: Yesterday was Sunday. II: Tomorrow is Tuesday. The answer is:
- A) Either alone is sufficient ✔
- B) I alone only
- C) II alone only
- D) Both needed
Why: I: yesterday Sunday → today Monday. II: tomorrow Tuesday → today Monday. Each statement alone gives the answer.
Matrix rows: 2,3,6 | 4,5,20 | 3,7,? The missing number is:
- A) 21 ✔
- B) 10
- C) 24
- D) 18
Why: Pattern: third = first × second (2 × 3 = 6, 4 × 5 = 20). So 3 × 7 = 21.
Matrix rows: 5,7,12 | 8,3,11 | 6,9,? The missing number is:
- A) 15 ✔
- B) 54
- C) 3
- D) 12
Why: Pattern: third = first + second (5 + 7 = 12, 8 + 3 = 11). So 6 + 9 = 15.
Matrix rows: 2,4,16 | 3,9,81 | 4,16,? The missing number is:
- A) 256 ✔
- B) 64
- C) 20
- D) 32
Why: Pattern: third = square of the middle number (4² = 16, 9² = 81). So 16² = 256.
Matrix rows: 9,3,3 | 16,4,4 | 25,5,? The missing number is:
- A) 5 ✔
- B) 25
- C) 10
- D) 125
Why: Pattern: the second and third numbers are the square root of the first (√9 = 3, √16 = 4). So √25 = 5.
Matrix rows: 10,4,6 | 15,7,8 | 20,9,? The missing number is:
- A) 11 ✔
- B) 29
- C) 12
- D) 9
Why: Pattern: third = first − second (10 − 4 = 6, 15 − 7 = 8). So 20 − 9 = 11.
An ordinary year has how many odd days?
- A) 1 ✔
- B) 2
- C) 0
- D) 3
Why: 365 days = 52 weeks + 1 day, so an ordinary year has 1 odd day. The same date moves forward one weekday next year.
A leap year has how many odd days?
- A) 2 ✔
- B) 1
- C) 0
- D) 3
Why: 366 days = 52 weeks + 2 days, so a leap year has 2 odd days.
Which of these is a leap year?
- A) 2000 ✔
- B) 1900
- C) 2100
- D) 2023
Why: 2000 is a leap year because century years must be divisible by 400, and 2000 ÷ 400 = 5.
Is 1900 a leap year?
- A) No ✔
- B) Yes
- C) Only in Nepal
- D) Only in February
Why: No. 1900 is divisible by 4, but century years must be divisible by 400, and 1900 is not.
Is 2024 a leap year?
- A) Yes ✔
- B) No
- C) Only half
- D) Cannot say
Why: Yes. 2024 ÷ 4 = 506, and it is not a century year, so it is a leap year with 29 days in February.
How many odd days are there in 100 years?
- A) 5 ✔
- B) 1
- C) 0
- D) 7
Why: 100 years have 24 leap years and 76 ordinary years: 24 × 2 + 76 × 1 = 124 odd days. 124 ÷ 7 leaves 5, so 5 odd days.
How many odd days are there in 400 years?
- A) 0 ✔
- B) 5
- C) 1
- D) 2
Why: 400 years have 97 leap years. Total odd days = 4 × 5 (for each 100 years) + 1 (the 400th year is a leap year) = 21, which is exactly 3 weeks, so 0.
Today is Monday. What day will it be after 10 days?
- A) Thursday ✔
- B) Wednesday
- C) Friday
- D) Tuesday
Why: 10 ÷ 7 leaves remainder 3. Monday + 3 days = Thursday.
Today is Friday. What day was it 15 days ago?
- A) Thursday ✔
- B) Friday
- C) Wednesday
- D) Saturday
Why: 15 ÷ 7 leaves remainder 1. Going back 1 day from Friday gives Thursday.
1 January 2025 was a Wednesday. What day was 1 January 2026?
- A) Thursday ✔
- B) Wednesday
- C) Friday
- D) Tuesday
Why: 2025 is an ordinary year (1 odd day), so the day moves forward by one: Wednesday + 1 = Thursday.
If 1 January of a leap year is Monday, 1 January of the next year is:
- A) Wednesday ✔
- B) Tuesday
- C) Thursday
- D) Monday
Why: A leap year has 2 odd days, so the day moves forward by two: Monday + 2 = Wednesday.
A month of 31 days has how many odd days?
- A) 3 ✔
- B) 1
- C) 2
- D) 0
Why: 31 = 4 weeks (28 days) + 3, so 3 odd days.
A month of 30 days has how many odd days?
- A) 2 ✔
- B) 3
- C) 1
- D) 0
Why: 30 = 28 + 2, so 2 odd days.
February in an ordinary year has how many odd days?
- A) 0 ✔
- B) 1
- C) 2
- D) 3
Why: 28 days = exactly 4 weeks, so 0 odd days. In a leap year (29 days) February has 1 odd day.
How many days does February have in a leap year?
- A) 29 ✔
- B) 28
- C) 30
- D) 31
Why: February has 29 days in a leap year instead of 28. This extra day makes the year 366 days.
Odd day number 0 corresponds to:
- A) Sunday ✔
- B) Monday
- C) Saturday
- D) Friday
Why: The standard code: 0 = Sunday, 1 = Monday, 2 = Tuesday, 3 = Wednesday, 4 = Thursday, 5 = Friday, 6 = Saturday.
Odd day number 4 corresponds to:
- A) Thursday ✔
- B) Wednesday
- C) Friday
- D) Tuesday
Why: Counting from Sunday = 0: 1 Monday, 2 Tuesday, 3 Wednesday, 4 Thursday.
If the 5th of a month is Tuesday, the 26th of that month is:
- A) Tuesday ✔
- B) Wednesday
- C) Monday
- D) Thursday
Why: 26 − 5 = 21 days, which is exactly 3 weeks, so the 26th is also a Tuesday.
If the 1st of a month is Sunday, which date is the third Sunday?
- A) 15th ✔
- B) 14th
- C) 21st
- D) 22nd
Why: Sundays fall every 7 days: 1st, 8th, 15th. So the third Sunday is the 15th.
15 August 1947 was a:
- A) Friday ✔
- B) Monday
- C) Sunday
- D) Wednesday
Why: 15 August 1947, India's Independence Day, was a Friday. It is a common example in odd-days questions.
A shop's profit was Rs 40,000 in one year and Rs 50,000 the next. The increase is:
- A) 25% ✔
- B) 20%
- C) 10%
- D) 50%
Why: Increase = 10,000. % increase = 10,000 ÷ 40,000 × 100 = 25%.
In a table, A = 30, B = 45, C = 75. What percentage of the total is C?
- A) 50% ✔
- B) 75%
- C) 25%
- D) 40%
Why: Total = 30 + 45 + 75 = 150. C's share = 75 ÷ 150 × 100 = 50%.
If a pie sector is 36°, its percentage is:
- A) 10% ✔
- B) 36%
- C) 3.6%
- D) 20%
Why: 36 ÷ 3.6 = 10%. Or 36/360 = 1/10 = 10%.
In data sufficiency, option "e" usually means:
- A) Even both statements together are not sufficient ✔
- B) Statement I alone is sufficient
- C) Either is sufficient
- D) Both together are sufficient
Why: In the usual five-option format, (e) means even both statements together are not enough to answer the question.