# 100+ Challenging math riddles to keep your mind sharp #### Triangle - Photo Math riddle

###### 17.Math Riddles

Which one will replace the question mark? • A.25
• B.37
• C.47
• D.41
D.41
• ```Explanation :  See the pattern in first triangle 5*3 +4 =19,

in the last triangle 6*4+5 = 29

then for this 7*5+6= 41```

#### Cup and Kite Alphabet - Math riddle

###### 19.Math Riddles

If CUP = 40, KITE =?

• A.10
• B.45
• C.25
• D.30
B.45
• ```Explanation :  45  By using forward letter position, we have,
CUP = C + U + P = 3 + 21 + 16 = 40.
Similarly, KITE = K + I + T + E = 11 + 9 + 20 + 5 = 45.```

#### Guess the Number -Math riddle

###### 20.Math Riddles

Can you solve this? • A.18
• B.19
• C.88
• D.96
D.96
• ```Explanation :  96
*1+1=5
so
11*8+8= 96```

#### Hard Mathematics -Math riddle

###### 21.Math Riddles

If

```123=0
4235=0
656=2
5390=2
8890=6
1001=2
19235=1
What is 123456789?```

• A.1
• B.2
• C.4
• D.5
C.4
• ```Explanation :  4
You need to count the number of closed circles.```

#### Person is 10 years old -Math riddle

###### 22.Math Riddles

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

•

```Explanation :  If a person was 15 in 1990 b.c.e/b.c
then in 1995 he/she will be 10 as years are counted backwards.```

#### Guess the Tom's age -Math riddle

###### 23.Math Riddles

In two years I know, I'll be twice as old as five years ago, said Tom. How old is Tom?

• A.12
• B.30
• C.40
• D.70
A.12
• ```Explanation :  Let Tom's age 5 years ago be x

Then Tom's current age = x + 5

Therefore Tom's age 2 years to come = 2(x) = 2x

From the above information:

Tom's current age + 2 years to come = Tom's age 2 years to come

(x + 5) + 2 = 2x, solving

x + 7 = 2x

x = 7

Hence Tom's age now = x + 5 = 7 + 5 = 12 years old.```

#### What is the value-Math riddle

###### 25.Math Riddles

What is the value of 1/2 of 2/3 of 3/4 of 4/5 of 5/6 of 6/7 of 7/8 of 8/9 of 9/10 of 1000?

• A.10
• B.300
• C.70
• D.100
D.100
• `Explanation :  D . 1/2*2/3*3/4 *4/5 *5/6 *6/7*7/8*8/9*9/10*1000 =100`

#### The Bare Feet Kids-Math riddle

###### 26.Math Riddles

There are 12 kids in a classroom. 6 kids are wearing socks and 4 are wearing shoes. 3 kids are wearing both. How many are bare feet?

• A. 10
• B. 7
• C. 20
• D. 5
D. 5
• ```Explanation :  As we know 3 kids are wearing both, So only 3 kids are wearing only socks(6 - 3 = 3) and 1 is wearing only shoes(4 - 3 = 1).

So, in total 3 + 3 + 1 = 7.

Now 12 are there, so 12 - 7 = 5 kids are in bare feet.```

#### The Coffin Problem -Math riddle

###### 27.Math Riddles

There are 500 coffins and 500 men who need them. The undertaker asks the first man to go to every coffin and open them. Then he tells the second man to go to every one and close it. The third one goes to every third coffin and so on. How many are open? • A.10
• B.32
• C.22
• D.50
C.22
• ```Explanation :  There aree 500 men. the open close and open process we have to count. we can take the root of 500.
So, 500 = 22.36.

#### Clothing Store in Dallas - Math riddle

###### 28.Math Riddles

There is a clothing store in Dallas. The owner has made his own method of pricing items. A vest costs \$20, socks cost \$25, a tie costs \$15, and a blouse costs \$30. Using the method, how much would a pair of underwear cost?

• A.100
• B.55
• C.45
• D.50
C.45
• `Explanation :   \$45 .The pricing method consists of charging \$5 for each letter required to spell the item`

#### Seven People handshakes-Math riddle

###### 29.Math Riddles

If seven people meet each other and each shake hands only once with each of the others, how many handshakes happened? • A.14
• B.49
• C.42
• D.21
D.21
• ```Explanation :  21.
The number of handshakes is equal to the previous number of people multiplied by the current number of people, divided by 2.
In algebraic terms, the formula is:
[n(n-1)]/2```

#### Cheaper Movie Ticket-Math riddle

###### 30.Math Riddles

If you go to the movies and you are paying, is it cheaper to take one friend to the movies twice or two friends to the movies at the same time?

• `Once`
`Explanation :  It's cheaper to take two friends at the same time. In this case, you would only be buying three tickets, whereas if you take the same friend twice, you are purchasing four tickets.`