Math Puzzles Questions

In the given puzzle, the logic is the product of the number and its preceeding number gives the result.

9 = 9 x 8 = 72

8 = 8 x 7 = 56

7 = 7 x 6 = 42

6 = 6 x 5 = 30

5 = 5 x 4 = 20

Similarly,

3 = 3 x 2 = 6.

 It is a strange sequence. Each number describes the resemblance of the previous one, except the first one.

11 describes the previous '1' which contains one '1'

21 describes the previous '11' which contains two '1'

1211 describes the previous '21' which contains one '2' and one '1'

111221 describes the previous '1211' which contains one '1', one '2' and two '1'.

So the next sequence will be 312211, that is the previous '111221' contains three '1', two '2' and one '1'.

In the given puzzle, the logic is

2 + 3 = 10 => (2 + 3) * 2 = 10

6 + 3 = 54 => (6 + 3) * 6 = 54

8 + 3 = 88 =>  (8 + 3) * 8 = 88

Similarly,

9 + 7  => (9 + 7) * 9 = 16 x 9 = 144.

NUMERICAL has 9 positions in which 2, 4, 6, 8 are even positions.

And it contains 5 consonents i.e, N, M, R, C & L. Hence this cannot be done as 5 letters cannot be placed in 4 positions.

Therefore, Can't be determined.

Let the two digits be x & y

From given data in the question, we get

x + y = 3(x - y)

x + y = 3x - 3y

=> 2x = 4y

x/y = 2/1

For having the 2:1, numbers satisfying are

12, 21, 24, 42, 36, 63, 48, 84

From this 36 is eleminated because it is a perfect square and no others are prime or perfect squares.

Hence, there exists 7 such 2-digit numbers => 12, 21, 24, 42, 63, 48, 84.

Let the required number be 'X'

Condition 1 :  

$$\begin{gathered} XX = 2X \\ => 2X2 = X \\ => X = 12 \end{gathered}$$

Condition 2 :

$$\begin{gathered} X × X = X2 \\ => X = 12 \end{gathered}$$

Therefore, 12 is the number which becomes double when it is divided by itself and becomes half when it is multiplied by itself.

Given two trains of length = 180 mts + 180 mts 

The distance is = Length of trains = 360 mts 

Speed = 58 - 50 = 8 kmph x 5/18 m/s

Then, Time = dis/speed = (360x18) / (8x5) = 162 sec.

In the given puzzle,

The logic is in the format of lets say, a/b

In that case b doesn't matter, because

2/2 = 1,

6/5 = 6/2 = 3,

10/11 = 10/2 = 5

This means that equation is a/2

So 16/19 is equal 16/2 = 8.