If 1*36=36

8*23=23

8*67=1

Then

9*10=?

# Number Puzzles

## Collection of best number puzzles

Number puzzles have specific set of rules, you first has to figure out the pattern being followed and then answer the puzzle according to the pattern.

Number puzzles are a part of many competitive examinations, these also helps you improve your logical thinking and above all these are fun to crack !!!

### Apply you mind and solve these number puzzles now

## Number Puzzle #177

## Find next number in following sequence

## What will be the next number in below sequence?

0, 1, 5, 19, 65, 211, ?

Check your answer:-

explanation:

it follows this equation

**3^n – 2^n**where n is integer starting from 0

thus

3^0 – 2^0 = 1 – 1 = 0

3^1 – 2^1 = 3 – 2 = 1

3^2 – 2^2 = 9 – 4 = 5

3^3 – 2^3 = 27 – 8 = 19

3^4 – 2^4 = 65

3^5 – 2^5 = 211

3^6 – 2^6 = 729 – 64 = 665

There is one more way to solve this

**3*previous number + 2^(n-1)**

0x3+1=1;

1×3+2=5;

5×3+4=19;

19×3+8=65;

65×3+16=211;

211×3+32=665;

**wondering how it is possible?**

lets solve 3*previous number + 2^(n-1)

=> 3*(3^(n-1) – 2^(n-1)) + 2^(n-1)

=> 3^n – (2+1)*2^(n-1) + 2^(n-1)

=> 3^n – 2^n – 2^(n-1) + 2^(n-1)

=> 3^n – 2^n i.e. our first equation

## How to buy six products from 20rs?

## How to buy six products from 20Rs. without using Paisa & without repeating numbers ?

## Find out the missing digit – 30 43 51 ?

Number Puzzle #175

find out the missing number

2 3 1 2

3 4 4 5

5 6 6 7

30 43 51 ?

## IF 5 7 3 20 10 30 then 95 45 ?

## Missing number Puzzle X 21 147

## Number Puzzle #173

2 6 18

4 20 100

X 21 147

find X

Check your answer:-

**Answer**: X = 3

**Solution**

in first row next number is a multiplication of 3 and the previous number

second row, next number is a multiplication of 5 and the previous number

in third row 3rd number (147) is a multiplication of 7 and previous number, i.e. 21, thus X*7 = 21 =>

**x = 21/7 = 3**

## Number Puzzle #172

### Let’s see who can crack this:-

If 10-2= 33

37-23=83

82-4= 43

55-7=32

then 76-45=?

## IF 1=2, 2 = 10, 3 = 30, 4=68 Then 5 =?

## Number Puzzle #171

Find out the numbers in the boxes

A | + | B | = | 8 |

+ | + | |||

C | – | D | = | 6 |

|| | || | |||

13 | 8 |

Check your answer:-

Top Left Box

Bottom Left Box

Bottom Right Box

Answer With Explanation

**Answer**:

3.5 | + | 4.5 | = | 8 |

+ | + | |||

9.5 | – | 3.5 | = | 6 |

|| | || | |||

13 | 8 |

**Explanation**:

We can make four equations

A+B = 8

C-D = 6

A+C = 13

B+D = 8

now we have four variables with four equations so it should be easy to solve. let’s solve these four equations

if we add the four equations

A+B+C-D+A+C+B+D = 8 + 6 + 13 + 8

2(A+B) + 2C = 35

2C = 35 – 2*8 —- by replacing A+B

2C = 35 – 16 = 19

C = 9.5

from 2nd Equation C – D = 6

D = C – 6

D = 9.5 – 6

D = 3.5

from 3rd equation

A+C = 13

A = 13 – C

A = 13 – 9.5

A = 3.5

from 4th equation

B + D = 8

B = 8 – D

B = 8 – 3.5

B = 4.5

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