Search Previous Year Questions

The correct answer is: 2

 

Given:

2, 18, 95, 384, 1155, ?

Calculation:

the series follows the following pattern:

2 x 6 + 6 = 18

18 x 5 + 5 = 95

95 x 4 + 4 = 384

384 x 3 + 3 = 1155

1155 x 2 + 2 = 2312

 

∴ 2312 will come in place of ?

The pattern of the series is as follows: +52, +102, +152, +202, +252

10 + 5² = 35

35 + 10² = 135

135 + 15² = 360

360 + 20² = 760

760 + 25² = 1385

∴ The required answer is 1385.

Given:

0.3 , 8.1 , 37.5 , ?  

Calculation:

In the given series the logic follows  is the cube of a odd numbers × 0.3

1³ $\times$ 0.3 = 1 $\times$ 0.3 = 0.3

3³ $\times$ 0.3 = 27 $\times$ 0.3 = 8.1 

5³ $\times$ 0.3 = 125 $\times$ 0.3 = 37.5

Hence the next value will be

73 $\times$ 0.3 = 343 $\times$ 0.3 = 102.9 

$\therefore$ The correct answer is 102.9 .

The pattern of the series is as follows: +6 × 1, +6 × 2, +6 × 4, +6 × 8, +6 × 16  

4 + 6 × 1 = 10

10 + 6 × 2 = 22

22 + 6 × 4 = 46

46 + 6 × 8 = 94

94 + 6 × 16 = 190

∴ The required answer is 94.

The given series is 7, 20 , 59 , 176

This series follows the pattern 

⇒ 7×3-1 =20

⇒ 20×3-1=59

⇒ 59×3 -1 = 176

Then next term of this series is 

⇒ 176×3-1 = 527

Hence 527 is the correct answer.

Given:

60% of the employees in a bank are officers

Remaining 40% of the employees are clerks

Daily wage of each clerk = Rs. 390

Daily wage of each officer = Rs. 720

Formula:

Average daily wage = Total daily wage / Total number of employess

Calculation:

Let, total number of employees = 100x

∴ Number of officers = 100x × 60 / 100 = 60x

∴ Number of clerks = (100x - 60x) = 40x

Let, average daily wage of all the employees = Rs. y

According to the question,

⇒ 100x × y = 60x × 720 + 40x × 390

⇒ 100y = 43200 + 15600

⇒ y = 432 + 156

⇒ y = 588

∴ Average daily wage of all the employees in the bank = Rs. 588

Shortcut Trick

Sum of ages after increases = 44 + 4 + 2 = 50 years.

New ratio is 2 ∶ 3 → Total parts = 5.

5 units = 50 ⇒ 1 unit = 10.

New ages: Hrick = 2 × 10 = 20, Oindrila = 3 × 10 = 30.

Present ages: Hrick = 20 − 4 = 16, Oindrila = 30 − 2 = 28.

Original ratio = 16 ∶ 28 = 4 ∶ 7.

∴ The correct answer is 4 ∶ 7.

Alternate Method

Given: Sum of Present Ages = 44 years. New Ratio = 2 ∶ 3 after adding 4 and 2 years respectively.

Calculations:

⇒ Let Hrick's present age be H and Oindrila's be O.

⇒ H + O = 44 — (Equation 1)

⇒ (H + 4) ÷ (O + 2) = 2 ÷ 3

⇒ 3(H + 4) = 2(O + 2)

⇒ 3H + 12 = 2O + 4 ⇒ 3H − 2O = −8 — (Equation 2)

⇒ From (1), O = 44 − H. Substitute in (2):

⇒ 3H − 2(44 − H) = −8

⇒ 3H − 88 + 2H = −8 ⇒ 5H = 80 ⇒ H = 16

⇒ O = 44 − 16 = 28

⇒ Ratio x ∶ y = 16 ∶ 28 = 4 ∶ 7

∴ The correct answer is 4 ∶ 7.

Additional Information

Ratio and Sum Relation

If the sum of two quantities is S and their ratio is a ∶ b, then the quantities are [a ÷ (a+b)] × S and [b ÷ (a+b)] × S.

Age Problems Shift

When ages are increased or decreased, the sum of ages changes by the total number of years added to or subtracted from each individual.

Given:

A man sells his goods at 20% profit

Formula used:

Selling Price = Cost Price (100% + Profit%)

Profit% = $\frac{Selling\ Price-Cost\ Price}{Cost\ Price} \times 100$

Calculation:

let the cost price be 100x,

A man sells his goods at 20% profit,

Selling Price = 100x (100% + 20%)

= $100x \times \frac{120}{100}$

= 120x

If the price at which he buys the goods increases by 30%,

Increased Cost Price =  100x (100% + 30%)

= $100x \times \frac{130}{100}$

= 130x

he sells them at an 15% higher price,

Increased Selling Price = 120x (100% + 15%)

= $120x \times \frac{115}{100}$

= 138x

Profit% = $\frac{138x-130x}{130x} \times 100$

= $\frac{8x}{130x} \times 100$

= $\frac{80}{13}$

= 6.15%(approx.)

Profit is 6.15%.

Answer is 6.15%.

Let assume time taken to travel downstream as x hr.,

Speed of boat in upstream = Speed of boat - speed of stream = 18 - 2 = 16 kmph

Speed of boat in downstream = speed of boat + speed of stream = 18 + 2 = 20 kmph

Time for upstream = x + 3 hr.

By the formula,

Distance = speed × time,

Distance in upstream + Distance in downstream = 320

⇒ 16 × (x + 3) + 20 × x = 320

⇒ 16x + 48 + 20x = 320

⇒ 36x = 320 - 48

⇒ 36x = 272

⇒ x = 7.56 hr

Time taken for upstream = x + 3 = 7.56 + 3 = 10.56 hr

∴ Upstream time in min = 10.56 × 60 = 633.6 min.

Given:

A construction company hired 1000 persons to construct a building in 77 days but the company realized after 44 days 40% of the work had been finished

Formula used:

$\frac{Person_1 \times Time_1}{Work_1}= \frac{Person_2 \times Time_2}{Work_2}$

Calculation:

let  the total work be 100% ,

40% of the work is completed in 44 days,

Then 60% of the work should be completed in remaining 33 days,

$\frac{1000 \times 44}{40\%}= \frac{Person_2 \times 33}{60\%}$

$\frac{1000 \times 44}{2}= \frac{Person_2 \times 33}{3}$

$Person_2=\frac{1000\times44\times3}{2\times33}$

= 2000

Increase in number of persons = 2000 - 1000

= 1000 persons

Company has to increase the number of persons by 1000 in order to finish the work on scheduled time.