## First WBCS math question set for Arithmetic practice

First WBCS Math Question Set with carefully selected 10 math questions of WBCS Mains exam. Take the timed test in all seriousness. Answers given.

Questions are on *Time work, LCM, Number system, Simplifications, Surds, indices, Square root, Ratio, Profit loss. *

It should be **useful for prelims of other competitive exams also.**

The **solution set** (linked at the end) explains how to solve the questions quickly in mind.

To refresh concepts on any topic and to know how to solve the questions quickly, you may refer to the **concept articles** listed at the end.

### 1st WBCS Math question set: time to answer is 10 mins

#### Problem 1

If A and B complete a job working together in 20 days, B and C together in 15 days and C and A in 12 days, all three working together will be able to complete the same job in,

- 9 days
- 10 days
- 10.5 days
- 6 days

#### Problem 2

If $x$ is a prime number, the LCM of $x$ and $(x+1)$ is,

- $x^2$
- $(x+1)^2$
- $\displaystyle\frac{x(x+1)}{2}$
- $x(x+1)$

#### Problem 3

$\left(2-\displaystyle\frac{1}{3}\right)\left(2-\displaystyle\frac{3}{5}\right)\left(2-\displaystyle\frac{5}{7}\right)...\left(2-\displaystyle\frac{999}{1001}\right)$ is equal to,

- $\displaystyle\frac{1003}{3}$
- $\displaystyle\frac{999}{1001}$
- $\displaystyle\frac{1001}{3}$
- None of these

#### Problem 4

The value of $\displaystyle\frac{\sqrt{32}+\sqrt{48}}{\sqrt{8}+\sqrt{12}}$ is,

- 2
- 4
- $\sqrt{2}$
- 8

#### Problem 5

The difference between the squares of two consecutive even integers is always divisible by,

- 3
- 4
- 6
- 7

#### Problem 6

The least number which when divided by 15, 27, 35, and 42 leaves a remainder of 7 in each division is,

- 1883
- 2007
- 1897
- 1987

#### Problem 7

$\left(\displaystyle\frac{243}{32}\right)^{-\displaystyle\frac{4}{5}}$ is equal to,

- $\displaystyle\frac{81}{16}$
- $\displaystyle\frac{16}{81}$
- $\displaystyle\frac{2}{9}$
- $\displaystyle\frac{9}{2}$

#### Problem 8

$\sqrt{248 +\sqrt{52 + \sqrt{144}}}$ is equal to,

- 16.6
- 16
- 14
- 18.8

#### Problem 9

The ratio of cost price to sale price is 20 : 23. What is the profit percentage?

- 20%
- 15%
- 5%
- 6%

#### Problem 10

$\sqrt[3]{0.000216}$ is equal to,

- 0.6
- 0.006
- 0.06
- 0.0006

Solutions to these problems with conceptual explanation, and how to solve the problems easily and quickly, are available in companion solution set,

* Solutions to WBCS Math Question Set 1*.

### Answers to the questions

**Problem 1. Answer:** Option b: 10 days.

**Problem 2. Answer:** Option d: $x(x+1)$.

**Problem 3.** **Answer:** Option a: $\displaystyle\frac{1003}{3}$.

**Problem 4. Answer:** Option a: 2.

**Problem 5.** **Answer:** Option b: 4.

**Problem 6.** **Answer:** Option c: 1897.

**Problem 7.** **Answer:** Option b: $\displaystyle\frac{16}{81}$.

**Problem 8.** **Answer:** Option b: 16.

**Problem 9.** **Answer:** Option b: 15%.

**Problem 10.** **Answer:** Option c: 0.06.

### Concept tutorials and articles on Arithmetic

#### Number system, fractions and surds

**Numbers, Number system and basic arithmetic operations**

**Factorization or finding out factors**

**Fractions and decimals, basic concepts part 1**

**How to solve surds part 1 rationalization**

**How to solve surds part 2 double square root surds and surd term factoring**

**How to find perfect square root of integers or decimals**

#### Ratio and proportion and mixing liquids

**Arithmetic problems on mixing liquids and based ages**

**How to solve arithmetic mixture problems in a few steps 1**

**How to solve arithmetic mixture problems in a few steps 2**

#### Percentage

**Basic and rich percentage concepts**

#### Componendo dividendo

**Componendo dividendo explained**

#### Simple interest and compound interest

**Basic and rich concepts on simple interest and compound interest**

#### Work time, work wages and pipes and cisterns

**How to solve arithmetic problems on work time, work wages and pipes and cisterns**

**How to solve time work problems in simpler steps type 1**

**How to solve time work problems in simpler steps type 2**

#### Speed time distance, train problems and boats in rivers

**Basic concepts on speed time distance, train running and boats and rivers**

**How to solve time distance problems in a few simple steps 1**

**How to solve time distance problems in a few simple steps 2**

#### Profit and loss

**How to solve in a few steps profit and loss problems 1**

**How to solve similar problems in a few seconds profit and loss problems 2**

**How to solve difficult profit and loss problems in a few steps 3**

**How to solve difficult profit and loss problems in a few steps 4**

#### Clocks and Calendars

**How to solve Calendar problems**

### Question and Solution sets on WBCS Arithmetic

**10 WBCS Math Questions - 12th Solved Arithmetic Practice Set**

**Solution to 11th set of WBCS Math Questions for Arithmetic Practice**

**11th set of WBCS Math Questions for Arithmetic Practice**

**Solution to 10th set of WBCS Math Questions for Arithmetic Practice**

**10th set of WBCS Math Questions for Arithmetic Practice**

**Solution to 9th set of WBCS Math Questions for Arithmetic Practice**

**9th set of WBCS Math Questions for Arithmetic Practice**

**Solution to 8th set of WBCS Math Questions for Arithmetic Practice**

**8th set of WBCS Math Questions for Arithmetic Practice**

**Solution to 7th set of WBCS Math Questions for Arithmetic Practice**

**7th set of WBCS Math Question for Arithmetic Practice**

**Solution to 6th set of WBCS Math Questions for Arithmetic Practice**

**6th set of WBCS Math Questions for Arithmetic Practice**

**Solution to 5th set of WBCS Math Questions for Arithmetic Practice**

**5th set of WBCS Math Questions for Arithmetic Practice**

**Solution to 4th set of WBCS Math Questions for Arithmetic Practice**

**4th set of WBCS Math Questions for Arithmetic Practice**

**Solution to 3rd set of WBCS Math Questions for Arithmetic Practice**

**3rd set of WBCS Math Questions for Arithmetic Practice**

**Solution to 2nd set of WBCS Math Questions for Arithmetic Practice**

**2nd set of WBCS Math Questions for Arithmetic Practice**

**WBCS Main level Arithmetic Solution set 1**

**WBCS Main level Arithmetic Question set 1**