Find real questions from previous competitive exam papers with answers and solutions.
Browse complete papersIf \(\frac{2}{5}\) of three-fourths of a number is 174, then what is that number?
232
326
435
580
Correct answer
580
Why this answer is correct
Given:
\(\dfrac{ 2}{5} \)of three-fourths of a number is 174
Calculation:
Let the number be X
⇒ \(\dfrac{ 2}{5} × \dfrac{3}{4} × X\) = 174
⇒ 2 × 3 × X = 174 × 5 × 4
⇒ X = \(\dfrac{174 × 4 × 5}{2 × 3} \)
⇒ X = 580
∴ That number is 580.
If \(\frac{3}{4}\) of \(\frac{2}{3}\) of a number is 782, then what is \(\frac{3}{5}\) of \(\frac{1}{4}\) of that number?
231
236.6
246.5
234.6
Correct answer
234.6
Why this answer is correct
Given:
\(\dfrac{3}{4}\) of \(\dfrac{2}{3}\) of a number is 782
Calculation:
Let, the unknown number be x.
⇒ \(\dfrac{3}{4} \) × \(\dfrac{2}{3} \) × x = 782
⇒ x = 3 × 2 = 782 × 4 × 3
⇒ x = \(\dfrac{782 × 4 × 3}{3 × 2} \)
⇒ x = 1564
Now, \(\dfrac{3}{5} \) of \(\dfrac{1}{4} \) of 1564
⇒ \(\dfrac{3}{5} \) × \(\dfrac{1}{4} \) × 1564 = 234.6
∴ Option (4) is the correct answer.
A student was asked to find out \(\frac{3}{2}\) of a number. He divided that number by \(\frac{3}{2}\). Due to this his result was 10 less than the correct answer. What is that number?
10
12
15
18
Correct answer
12
Why this answer is correct
Given:
The student was asked to multiply by a number = \(\dfrac{3}{2} \)
But he divides the number = \(\dfrac{3}{2} \)
Calculation:
Let the number be 'x'.
Number when multiply by \(\dfrac{3}{2} \) = \(\dfrac{3x}{2} \)
Number when divide by \(\dfrac{3}{2} \)= \(\dfrac{x}{ \dfrac{3}{2} } \) = \(\dfrac{2x}{3} \)
According to the question,
⇒\(\dfrac{3x}{ 2} \) –\(\dfrac{2x}{ 3} \) = 10
⇒\(\dfrac{9x-4x}{6} \) = 10
⇒ 5x = 60
⇒ x = 12
∴ The number was 12.
If x * y = 3x + 2y then 2 * 3 + 3 * 4 = ?
18
29
32
38
Correct answer
29
Why this answer is correct
Given:
x * y = 3x + 2y then 2 * 3 + 3 * 4 = ?
Calculation:
x * y = 3x + 2y
2 * 3 = 3 × 2 + 2 × 3 = 6 + 6 = 12
3 * 4 = 3 × 3 + 2 × 4 = 9 + 8 = 17
Now, 2 * 3 + 3 * 4 = 12 + 17 = 29
∴ 2 * 3 + 3 * 4 = 29
The cost of 24 bats and 32 hockey sticks is Rs. 8400. What is the cost of 3 bats and 4 hockey sticks ?
Rs. 2100
Rs. 4200
Rs. 1050
Cannot be determined
Correct answer
Rs. 1050
Why this answer is correct
Given:
The cost of 24 bats and 32 hockey sticks is Rs. 8400.
Calculation:
According to the question,
⇒ 24 b + 32 h = 8400 →(1)
Divide the equation by 8
⇒ \(\dfrac{24\text{b}}{8} \) + \(\dfrac{ 32\text{h}}{8} \) = \(\dfrac{ 8400}{8} \)
⇒ 3b +4h = 1050
∴ The cost of 3 bats and 4 hockey sticks is Rs. 1050.
The average age of 80 children in a class is 15 years. Out of these, the average age of a group of 15 children is 16 years and the average age of another 25 children of the class is 14 years. What is the average age of the remaining children of the class?
15.25 years
14 years
14.75 years
Cannot be determined
Correct answer
15.25 years
Why this answer is correct
Given:
The average age of 80 children in a class is 15 years.
The average age of a group of 15 children is 16 years.
The average age of the other 25 children in the class is 14 years.
Formula used:
Average = Sum of Observations/Number of Observations
Calculation:
Total age of 80 children = 80 × 15 = 1200 years.
Total age of 15 children = 15 × 16 = 240 years
Total age of 25 children = 25 × 14 = 350 years
Remaining children = 80 - 15 - 25 = 40
∴ The average age of the remaining 40 children = \(\dfrac{ 1200 - 240 - 350 }{40} \)
⇒ \(\dfrac{ 610}{40} \) = 15.25 years
∴ The average age of the remaining children in the class is 15.25 years.
The ratio between the speeds of a car, a jeep and a tractor is 3 ∶ 5 ∶ 2 respectively. The speed of the Jeep is 250% of the speed of the tractor. The tractor covers a distance of 360 km in 12 hours. What is the average of speed of the car and the Jeep?
60 km/h
86 km/h
40 km/h
Cannot be determined
Correct answer
60 km/h
Why this answer is correct
Given:
The ratio between the speeds of car, jeep, and tractor is 3 ∶ 5 ∶ 2 respectively.
The speed of the Jeep is 250% of the speed of the tractor.
The tractor covers a distance of 360 km in 12 hours.
Formula used:
Distance = Speed × Time
Calculation:
The tractor covers a distance of 360 kilometers in 12 hours.
The speed of the tractor = \(\dfrac{ 360}{12} \)= 30 km/hour.
The speed of the Jeep = \(\dfrac{250}{100} \)× speed of tractor = \(\dfrac{250}{100} \) × 30 = 75 km/hour.
We know that if the speed of the tractor is 2 units, the speed of the Jeep is 5 units.
According to Question,
1 unit of speed = \(\dfrac{30}{2} \) = 15 km/hour
The speed of the car = 3 × 15 = 45 km/hour.
The average of speed of the car and the Jeep = \(\dfrac{75+45}{2} \) = 60 km/hr
∴ The average speed of the car and the Jeep is 60 km/hr.
3 litres of sugar solution contains 40% sugar. If one litre of water is added to this solution, what will be the percentage of sugar in the new solution?
\(13\frac{1}{3}%\)
15%
30%
33%
Correct answer
30%
Why this answer is correct
Given:
The initial volume of solution = 3 litres.
Percentage of sugar in the solution = 40%.
The volume of water added = 1 litre.
Calculation:
Amount of sugar = 40% of 3L = \(\dfrac{40}{100} \times 3 \) = 1.2 litres.
New total volume = Initial volume + Added volume
⇒ 3L + 1L = 4 litres
New percentage of sugar = (Sugar Volume/Total Volume) × 100
⇒ \(\dfrac{1.2}{4} \times 100\) = 30%
∴ When 1 litre of water is added to this solution then the percentage of sugar will be 30%.
On increasing the length of a rectangle by 10% and decreasing the breadth by 10%, the area of the new rectangle :
will increase by 1%
will decrease by 1%
there will be a decrease of 10%
there will be neither decrease nor increase
Correct answer
will decrease by 1%
Why this answer is correct
Given:
Increment in length = 10% and Decrement in breadth = 10%
Formula used:
Use Successive Percentage:
Percentage change = (A + B + AB/100)%
Calculation:
According to the question,
A = 10% and B = - 10%
Percentage change = [10 - 10 + (10 × -10)/100]% = - 1%
∴ The area of the new rectangle is decreased by 1%.
A person sold two articles - article A at 40% profit and article B at 20% loss. He made a profit of Rs. 18 in the whole transaction. If the cost price of article A is Rs. 140 less than that of article B, then what is the cost price of article B?
Rs. 380
Rs. 280
Rs. 340
Rs. 370
Correct answer
Rs. 370
Why this answer is correct
Given:
Profit on article A = 40%
Loss on article B = 20%
Total Profit = Rs. 18
Cost Price of A = Cost Price of B - Rs. 140
Formula used:
Selling Price for profit = CP × (1 + Profit%)
Selling Price for loss = CP × (1 - Loss%)
Calculation:
Let CP of B = x So, CP of A = x - 140
SP of A with 40% profit = (x - 140) × 1.4
SP of B with 20% loss = x × 0.8
Total profit = (SP of A + SP of B) - (CP of A + CP of B)
⇒ 18 = ((x - 140) × 1.4 + x × 0.8) - (x - 140 + x)
⇒ 18 = 1.4x - 196 + 0.8x - 2x + 140
⇒ 18 = 0.2x - 56
⇒ 0.2x = 18 + 56
⇒ 0.2x = 74
⇒ x = 74/0.2 = 370
∴ The cost price of article B is Rs. 370.