Quantitative Aptitude PYQs

Paresh does 40% work in 10 days

Paresh can do the 100% work in

\( = \frac{{10}}{{1 \times \left( {\frac{{40}}{{100}}} \right)}}\)

=10 × 100/40 = 25 days

Rest work =1 – (4/10) = 6 / 10 = 3 / 5

Paresh & Bhave finished the remaining work in 6 days

The whole work will be done by Paresh & Bhave in 5/3 × 6 = 10 days

Paresh’s 1 day’s work = 1/25

And (Paresh + Bhave)’s 1 day’s work = 1/10

∴ Bhave’s 1 day’s work = (1/10) – (1/25)

= 15 / 250

∴ Bhave will do the whole work in 16 2/3 days

Given:

Saving of Rahul = Rs. 9600

Expenditure on Shopping = 15%

Expenditure on School fees = 20% of the remaining = 20% of 85% = 17%

Expenditure on other items = 20%

Concept:

Income = Expenditure + Saving

Calculation:

Let total income be 100%

Savings = 100% – (15% + 17% + 20%)

⇒ 100% – 52%

⇒ 48%

Now, 48% = Rs. 9600

⇒ 100% = 20000

∴ The required result will be Rs. 20,000

Let the length of train be x

Then, the length of platform is also x

Speed of train = 54 km/hr = 54 × (5/18) m/s = 15 m/s

∴ According to question

(x + x)/15 = 36

⇒ 2x = 540

⇒ x = 270 m

The length of the platform is 270 m

Now, a train of length 230 m crosses the platform in 25 sec

Let the speed of train be v m/s

⇒ (270 + 230)/v = 25

⇒ v = 20m/s

Speed of train = 20 m/s = 20 × (18/5) = 72 km/hr

∴ The speed of the train is 72 km/hr

Given:

8, 27, 64, 343, 1331.

Calculation:

The logic follows here is:

(2)³ = 8

(3)³ = 27

(5)³ = 125

(7)³ = 343

(11)³ = 1331

By observing the above pattern, we can see that

Except 64, all numbers are cube of prime numbers

∴ 64 is the wrong term.

Given:

8, 4, 4, 8, 33, 256

Calculation:

The series follows the following pattern,

8 × (1/2) = 4

4 × 1 = 4

4 × 2 = 8

8 × 4 = 32 ≠ 33

32 × 8 = 256

Since 32 will come in place of 33

∴ The required wrong number will be 33.

Given:

25, 27, 33, 40, 51, 65

Calculation:

The pattern of the given series can be expressed as,

Since 32 will come in place of 33

∴ The required wrong number will be 33.

Given:

50, 51, 59, 86, 140

Calculation:

The series follows the following pattern,

50 + 1³ = 51

51 + 2³ = 59

59 + 3³ = 86

86 + 4³ = 150 ≠ 140

Since 150 will come in place of 140

∴ The required wrong number will be 140.

Given:

154, 145, 161, 136, 174, 123, 187

Calculation:

The series follows the following pattern

⇒ 154 - 3² = 145

⇒ 145 + 4² = 161

⇒ 161 - 5² = 136

⇒ 136 + 6² = 172 ≠ 174

⇒ 172 - 7² = 123

⇒ 123 + 8² = 187

∴ 174 is wrong and should be replaced by 172.

Alternate Method

∴ 174 is wrong and should be replaced by 172.

Calculation:

Number of laptops sold in 2010 = 150

Number of laptops sold in 2014 = 350

Percentage increase = \(\frac{350 - 150}{150} \times 100 = \frac{200}{150} \times 100 = 133.33%\)

Answer: 133.33%

Calculation:

Total laptops sold over 5 years = 150 + 250 + 200 + 300 + 350 = 1250

Average = \( \frac{1250}{5} = 250\)

Answer: 250 laptops

Calculation:

Number of laptops sold in 2013 = 300

Revenue per laptop without discount = ₹15,000

Revenue lost per laptop due to 10% discount = 15,000 × 10% = ₹1,500

Total revenue lost = 300 × ₹1,500 = ₹450,000

Answer: ₹450,000

Calculation:

Highest sales = 350 (in 2014)

Lowest sales = 150 (in 2010)

Difference = 350 - 150 = 200

Answer: 200 laptops

Calculation:

Total laptops needed for an average of 320 over 6 years = 320 × 6 = 1920

Total laptops sold from 2010 to 2014 = 150 + 250 + 200 + 300 + 350 = 1250

Laptops needed in 2015 = 1920 - 1250 = 670

Answer: 670 laptops

Given :

Quantity of mixture = 20 L

Ratio of milk and water = 2 : 3

Calculations :

Quantity of milk = (2/5) × 20 = 8 L

Quantity of water in mixture = 20 - 8 = 12 L

Let x L of water be mixed

⇒ 8/(12 + x) = 1/3

⇒ x = 12

∴ 12 L of water should be mixed.

Given:

A is 4 years older than B.

The sum of present age of A and C is 48 years.

The ratio of present age of B and C is 7 : 4.

Calculation:

Let the age of A be x.

The age of C = 48 - x

A is 4 years older than B.

The age of B = x - 4

The ratio of present age of B and C is 7 : 4.

⇒(x - 4)/(48 - x) = 7/4

⇒ 4x - 16 = 336 - 7x

⇒ 11x = 352

⇒ x = 32

The age of A two years ago = 32 - 2 = 30 years

∴ The age of A two years ago is 30 years.

Given:

Speed in downstream = 30 km/h

Speed in upstream = 20 km/h

Formula:

Speed of downstream = Speed of a boat in still water + Speed of water current

Speed of upstream = Speed of a boat in still water - Speed of water current

Speed = Distance/Time

Calculation:

Let the speed of the boat in still water be x km/h and speed of water current be y km/h

Now, according to question

x + y = 30  ----(1)

x – y = 20  ----(2)

Now,

From equation (1) and (2), we get

⇒ 2x = 50

⇒ x = 50/2

⇒ x = 25

∴ The Speed of the boat in still water is 25 km/h

Calculation:

The product is sold at a 20% discount.

Discounted price = MP - 20% of MP = 3750 - (20/100 × 3750)

= 3750 - 750 = ₹3000

So, Selling Price (SP) = ₹3000

Profit = SP - CP

CP = SP - Profit

CP = ₹3000 - ₹250 = ₹2750

Difference = MP - CP

Difference = ₹3750 - ₹2750 = ₹1000

Answer: The difference between the marked price and the cost price is ₹1000.

Concept used:

Follow BODMAS rule to solve this question, as per the order given below:

494 - 15 × 8 + 43 - 77 = ?2

⇒ 494 - 120 + 64 - 77 = ?2

⇒ 494 -120 - 13 = ?2

⇒ 494 - 133 = ?2

⇒ 361 = ?2

∴ The value of ? is 19.

Given:

336 ÷ 24 × ∛343 + (7)2 = ?

Concept:

Follow BODMAS rule to solve this question, as per the order given below, 

Calculation:

336 ÷ 24 × ∛343 + (7)2 = ?

⇒ 14 × 7 + 49 = ?

⇒ 98 + 49 = ?

∴ ? = 147

GIVEN :

\(1{2 \over 13}\)× 338 + ? = 92 × 3 + 237

CONCEPT :

CALCULATION :

\(1{2 \over 13}\) × 338 + ? = 92 × 3 + 237

⇒ 15/13 × 338 + ? = 243 + 237

⇒ 390 + ? = 480

⇒ ? = 90