Arithmetic, number systems, percentages, ratios, profit and loss, time and work, algebra, geometry, mensuration, and trigonometry.
What will come in the place of the question mark ‘?’ in the following question?
115% of 4880 – 85% of 1640 = ?
4218
4368
4448
46228
None of these
Correct answer
4218
Why this answer is correct
Calculations:
115% of 4880 – 85% of 1640 = ?
⇒ (115/100) × 4880 – (85/100) × 1640 = ?
⇒ 5612 – 1394 = ?
⇒ ? = 4218
∴ The value of ? is 4218
What will come in the place of the question mark ‘?’ in the following question?
?% of 590 + 36% of 170 = 150
14.6
16.4
17.8
15.05
None of these
Correct answer
15.05
Why this answer is correct
Calculations:
?% of 590 + 36% of 170 = 150
⇒ (?/100) × 590 + (36/100) × 170 = 150
⇒ (59 × ?)/10 + 612/10 = 150
⇒ 59 × ? + 612 = 1500
⇒ 59 × ? = 888
⇒ ? = 15.05
∴ The value of ? is 15.05
What will come in the place of the question mark ‘?’ in the following question?
(102 - 68) + 46 = ? × 10
6
5
3
2
8
Correct answer
8
Why this answer is correct
Concept Used:
Follow BODMAS rule to solve this question, as per the order given below:
Calculation:
⇒ (102 - 68) + 46 = ? × 10
⇒ 34 + 46 = ? × 10
⇒ 80/10 = ?
⇒ ? = 8
∴ The required value of "?" is 8
What will come in place of question mark (?) in the following question?
852 - 13 × 8 - 102 × 3 - 1 = ?2
21
23
24
20
19
Correct answer
21
Why this answer is correct
Concept Used:
Calculation:
⇒ 852 - 13 × 8 - 102 × 3 - 1 = ?2
⇒ 852 - 104 - 306 -1 = ?2
⇒ 441 = ?2
⇒ 21 = ?
What will come in the place of the question mark ‘?’ in the following question?
60 - 38 ÷ 19 × 26 = ?
8
6
5
4
9
Correct answer
8
Why this answer is correct
Concept Used:
Follow BODMAS rule to solve this question, as per the order given below:
Calculation:
⇒ 60 - 38 ÷ 19 × 26 = ?
⇒ 60 - 2 × 26 = ?
⇒ 60 - 52 = ?
⇒ ? = 8
∴ The required value of "?" is 8
What will come in the place of the question mark ‘?’ in the following question?
163 + 7 × 11 - 9 = ? × 11
11
21
35
25
43
Correct answer
21
Why this answer is correct
Concept Used:
Follow BODMAS rule to solve this question, as per the order given below:
Calculation:
⇒ 163 + 7 × 11 - 9 = ? × 11
⇒ 163 + 77 - 9 = ? × 11
⇒ 240 - 9 = ? × 11
⇒ 231/11 = ?
⇒ ? = 21
∴ The required value of "?" is 21
What will come in place of question mark (?) in the following question?
312 - 928 - 52 = 2 × ? ÷ 11
22
34
45
44
76
Correct answer
44
Why this answer is correct
Concept Used:
Calculation:
312 - 928 - 52 = 2 × ? ÷ 11
⇒ 961 - 928 - 25 = 2 × ? /11
⇒ 33-25 = 2 × ? /11
⇒ 8 × 11 / 2 = ?
⇒ ? = 44
What will come in the place of the question mark ‘?’ in the following question?
39% of 700 + 12 = 5 × ?
43
57
54
55
66
Correct answer
57
Why this answer is correct
Concept Used:
Follow BODMAS rule to solve this question, as per the order given below:
Calculation:
⇒ 39% of 700 + 12 = 5 × ?
⇒ (39/100) × 700 + 12 = 5 × ?
⇒ 39 × 7 + 12 = 5 × ?
⇒ 273 + 12 = 5 × ?
⇒ ? = 285/5
⇒ ? = 57
∴ The required value of "?" is 57
What will come in place of the question mark (?) in the following question?
√676 × √576 – ? × 18 = 300
14
16
18
20
22
Correct answer
18
Why this answer is correct
Given
√676 × √576 – ? × 18 = 300
⇒ 26 × 24 - ? × 18 = 300
⇒ 624 - ? × 18 = 300
⇒ ? × 18 = 324
∴ ? = 18.
What will come in place of the question mark (?) in the following question?
24 + √81 ÷ 3 × ? = 30
1
2
3
4
5
Correct answer
2
Why this answer is correct
Given
24 + √81 ÷ 3 × ? = 30
⇒ 9 ÷ 3 × ? = 6
⇒ 3 × ? = 6
∴ ? = 2.
What will come in place of question mark (?) in the following question?
4 × (?/100) × 210 + 225 = 351
15
21
25
12
18
Correct answer
15
Why this answer is correct
Given
4 × (?/100) × 210 + 225 = 351
⇒ 4 × (?/100) × 210 = 126
⇒ ? = (126 × 100)/(4 × 210)
∴ ? = 15.
Two trains cross each other in 16 seconds coming from opposite directions. If the sum of their speeds is 25 m/s and train B is 60 m shorter than train A, then find the length of train A.
235 m
240 m
250 m
230 m
210 m
Correct answer
230 m
Why this answer is correct
Shortcut Trick
Total distance (Sum of lengths) = Relative Speed × Time
LA + LB = 25 × 16 = 400 m
Since LA − LB = 60 m, then LA = (Sum + Difference) ÷ 2
LA = (400 + 60) ÷ 2 = 230 m
∴ The correct answer is 230 m.
Alternate Method
Given:
Sum of speeds (Relative Speed) = 25 m/s
Time to cross = 16 s
Difference in lengths (LA − LB) = 60 m
Formula Used:
Distance = Speed × Time
Calculations:
⇒ Total Distance = Length of Train A (LA) + Length of Train B (LB)
⇒ LA + LB = 25 × 16
⇒ LA + LB = 400 m --- (Equation 1)
⇒ Given: LA − LB = 60 m --- (Equation 2)
⇒ Adding Eq 1 and Eq 2: 2 × LA = 400 + 60
⇒ 2 × LA = 460
⇒ LA = 230 m
∴ The correct answer is 230 m.
Additional Information
Relative Speed Concept
When two objects move in opposite directions, their relative speed is the sum of their individual speeds (S1 + S2). If they move in the same direction, it is the difference (S1 − S2).
Crossing Rule
When two trains cross each other, the total distance covered is always the sum of their lengths (L1 + L2), regardless of direction.
Unit Conversion
To convert km/hr to m/s, multiply by 5/18. To convert m/s to km/hr, multiply by 18/5.
If each side of a wooden job which is rectangular in shape is increased by 40%, then the percentage increase in the area of a rectangle wooden job is:
70%
65%
80%
96%
None of these
Correct answer
96%
Why this answer is correct
Shortcut Trick
Apply the successive percentage change formula: Net % change = x + y + (x × y) ÷ 100
Here, both length and breadth increase by 40%, so x = 40 and y = 40.
Net % increase = 40 + 40 + (40 × 40) ÷ 100
Net % increase = 80 + 1600 ÷ 100 = 80 + 16 = 96%.
∴ The correct answer is 96%.
Alternate Method
Given: Increase in each side of the rectangular wooden job = 40%.
Formula Used: Area of Rectangle = Length × Breadth.
⇒ Let original Length (L) = 10 and Breadth (B) = 10.
⇒ Original Area = 10 × 10 = 100 units2.
⇒ New Length = 10 + 40% of 10 = 14.
⇒ New Breadth = 10 + 40% of 10 = 14.
⇒ New Area = 14 × 14 = 196 units2.
⇒ Percentage increase in area = [(196 − 100) ÷ 100] × 100 = 96%.
∴ The correct answer is 96%.
Additional Information
Successive Percentage Change
When a value is changed by x% and then y%, the net change is given by [x + y + (xy/100)]%.
Area of 2D Figures
For any 2D shape where dimensions are increased by k%, the area increases by [2k + (k2/100)]%.
Fraction Method
40% increase means the multiplier is 1.4. For area (two dimensions), the multiplier becomes 1.4 × 1.4 = 1.96, indicating a 96% increase.
If A can fill 2/3 of a tank in 6 hours while B can fill 4/9th of the tank in 8 hours, find the time to fill 1/3 of the tank when both A and B work. (in hours).
1
1.5
2
2.5
None of the above/More than one of the above
Correct answer
2
Why this answer is correct
Shortcut Trick
Time taken by A to fill the full tank = 6 × (3/2) = 9 hours.
Time taken by B to fill the full tank = 8 × (9/4) = 18 hours.
Combined efficiency of A and B on total work of 18 units is 2 + 1 = 3 units/hour.
Time to fill 1/3 of the tank = (18 ÷ 3) × 3 = 6 ÷ 3 = 2 hours.
∴ The correct answer is 2 hours.
Alternate Method
Given:
Time taken by A to fill 2/3 of the tank = 6 hours
Time taken by B to fill 4/9 of the tank = 8 hours
Formula Used:
Total work = Efficiency × Time
Calculations:
⇒ Time taken by A to fill the complete tank = 6 × (3 ÷ 2) = 9 hours
⇒ Time taken by B to fill the complete tank = 8 × (9 ÷ 4) = 18 hours
| Person | Days | Total Work | Efficiency |
|---|---|---|---|
| A | 9 hours | 18 units | 2 units/hour |
| B | 18 hours | 1 unit/hour |
⇒ Combined efficiency of A and B = 2 + 1 = 3 units/hour
⇒ Work to be completed = 1/3 of total work = 18 ÷ 3 = 6 units
⇒ Time required for A and B together = 6 ÷ 3 = 2 hours
∴ The correct answer is 2 hours.
Additional Information
Pipes and Cisterns Concept
Inflow pipes have positive efficiency, whereas outflow or leak pipes have negative efficiency. The net work done is the sum of their individual efficiencies.
Work-Time Relation
If a person completes a fraction 1/x of work in y days, then the total time required to complete the entire work is x × y days.
There are two vessels- A and B containing milk and water in the ratio 8 : 7 and 4 : 5 respectively. In what ratio should they be mixed so that the ratio of milk and water in the resultant solution is 1 : 1?
3 : 5
4 : 3
5 : 3
2 ; 1
1 : 1
Correct answer
5 : 3
Why this answer is correct
Shortcut Trick
Apply Alligation on the fraction of milk in each vessel.
Vessel A milk fraction = 8/15 | Vessel B milk fraction = 4/9 | Resultant milk fraction = 1/2.
Common denominator for 15, 9, 2 is 90. Fractions become: 48/90, 40/90, 45/90.
Ratio = (45/90 − 40/90) : (48/90 − 45/90) = 5/90 : 3/90 = 5 : 3.
∴ The correct answer is 5 : 3.
Alternate Method
Given: Ratio in A = 8:7, Ratio in B = 4:5, Target Ratio = 1:1.
Formula: Quantity A / Quantity B = (m2 − m) / (m − m1)
⇒ Milk in A = 8/(8+7) = 8/15
⇒ Milk in B = 4/(4+5) = 4/9
⇒ Milk in mixture = 1/(1+1) = 1/2
⇒ Ratio = (1/2 − 4/9) : (8/15 − 1/2)
⇒ Ratio = (9 − 8)/18 : (16 − 15)/30
⇒ Ratio = 1/18 : 1/30 = 30 : 18 = 5 : 3
∴ The correct answer is 5 : 3.
Additional Information
Rule of Alligation
It is used to find the ratio in which two ingredients at given prices/concentrations must be mixed to produce a mixture at a mean price/concentration.
Mixture Concentration
When mixing liquids, focus on one component (either milk or water) consistently across all parts of the calculation to ensure accuracy.
Find the wrong term in the following series.
100, 91, 81, 70, 60, 45
91
81
60
70
45
Correct answer
60
Why this answer is correct
Given series:
100, 91, 81, 70, 60, 45
Calculation :
The series follows the following pattern:
⇒ 100 - 9 = 91
⇒ 91 - 10 = 81
⇒ 81 - 11 = 70
⇒ 70 - 12 = 58
⇒ 58 -13 = 45
The wrong term is 60
Hence the wrong term in the series is 60.
Find the wrong term in the following series.
98, 128, 162, 200, 242, 266
98
266
162
128
200
Correct answer
266
Why this answer is correct
Given series:
98, 128, 162, 200, 242, 266
Calculation :
The series follows the following pattern:
⇒ 49 + 49 = 98
⇒ 64 + 64 = 128
⇒ 81 + 81 = 162
⇒ 100 + 100 = 200
⇒ 121 + 121 = 242
⇒ 144 + 144 = 288
The wrong term is 266
Hence the wrong term in the series is 266.
Find the wrong term in the following series.
64, 100, 134, 161, 180, 189
100
64
161
180
189
Correct answer
100
Why this answer is correct
Given series:
64, 100, 134, 161, 180, 189
Calculation :
The series follows the following pattern:
The wrong term is 100
Hence the wrong term in the series is 100.
Find the wrong term in the following series.
12, 25, 50, 150, 600, 3000
12
25
50
600
150
Correct answer
12
Why this answer is correct
Given series:
12, 25, 50, 150, 600, 3000
Calculation :
The series follows the following pattern:
⇒ 25 x 1 = 25
⇒ 25 x 2 = 50
⇒ 50 x 3 = 150
⇒ 150 x 4 = 600
⇒ 600 x 5 = 3000
Hence the wrong term in the series is 12.
Find the wrong term in the given series.
145, 168, 197, 224, 252, 288
197
145
252
168
224
Correct answer
252
Why this answer is correct
Solution :
The series follows the following pattern :
⇒122 + 1 = 145
⇒132 - 1 = 168
⇒142 + 1 = 197
⇒152 - 1 = 224
⇒162 + 1 = 257
⇒172 - 1 = 288
⇒ The wrong term in the series will be 252.
Hence, 252 is the correct answer.
Solving previous year questions by topic helps identify recurring concepts, question patterns, and frequently asked sub-topics. Attempt each question, review the step-by-step explanation, and note down key formulas or facts for quick revision before the exam.