Math shortcuts, Articles, worksheets, Exam tips, Question, Answers, FSc, BSc, MSc

#### Keep Connect with Us

• =

• Welcome in Math School.
• This is beta verion of our website.
##### Fill the box using (1, 3, 5, 7 ,9, 11, 13, 15) ?

___________________________________________

```     (3+3) + (3+3) + (3+3) + (3+3) + (3+3) = 30
```
##### Explanation

This is an interesting question this kind of question was already asked in india's compitative exam UPSC(IAS/IPS) in year 2013. And only toper of this exam can solve it.

The following are the numbers that you can use to fill in the brackets: 1, 3, 5, 7, 9, 11, 13 and 15. You can repeat the numbers if required. The resulting sum should be 30.

```    (15-9)+(13-7)+(7-1)+(9-1)+(13-9)=30
```

If you solve inside the brackets, you will get the following equation 6 + 6 + 6 + 8 + 4 and by adding all these numbers you will get 30.

```    or
(7-1)+(15-9)+(11-5)+(13-3)+(3-1) = 30
```

This is not mention in above question that you can use sign or not. Thus we can use the sign (+, -, x etc ).
Because in the given question it is also mention that we can repeated the numbers. So wee can also solve it as...

```    (3+3) + (3+3) + (3+3) + (3+3) + (3+3) = 30
```

The above solution is best and easy way.

___________________________________________

##### Miscellaneous Short Questions

###### Famous Question IAS topper Gaurav Agrawal

______________________

###### Same Question IAS topper Gaurav Agrawal

______________________

###### If Y+1=3 then y = 2 ? (is not simple)

______________________

###### Mr. Khan's logical question?

______________________

##### Miscellaneous Short Questions

###### Math puzzle

______________________

###### -(-a) is read as ...?

______________________

###### If √(0.04)(0.4)a = (0.4)(0.04)√b then a/b ... ?

______________________

###### 3 ÷ (5 ÷ 7) = (3 ÷ 5) ÷ 7

______________________

###### Which step is wrong?

______________________

##### SHORTCUT TRICKS (Division)
• Divisible by 2 Shortcut trick
• Divisible by 3 Shortcut trick
• Divisible by 4 Shortcut trick
• Divisible by 5 Shortcut trick
• Divisible by 6 Shortcut trick
• Divisible by 7 Shortcut trick
• Divisible by 8 Shortcut trick
• Divisible by 9 Shortcut trick
• Divisible by 10 Shortcut trick