# 100+ Challenging math riddles to keep your mind sharp #### Tricky Daughter and Mother's age-Math riddle

###### 47.Math Riddles

The sum of a daughter and mother's age is 55. The age of the daughter is the mother's age reversed. Find the age of the mother and daughter, if the age of the mother is greater than 40 years.

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```Explanation :  The total of the mother's age and the daughter?? age is 50.
5 years ago, the mother was 7 times the age of the daughter.
Therefore,
If the total of their ages is 50 now, then 5 years ago the total of their ages was 40 (50 years minus 5 years off the mother's age and 5 years off the daughter?? age, or 50 (5+5)).
That last point is what will help us solve this problem. Let's state the last point as an equation. For the purposes of crafting some nice tidy equations, I?? going to say that:
M=Mother?? age five years ago
The total of the mother's age and the daughter?? age is 50.
5 years ago, the mother was 7 times the age of the daughter.
Therefore,
If the total of their ages is 50 now, then 5 years ago the total of their ages was 40 (50 years minus 5 years off the mother's age and 5 years off the daughter?? age, or 50 (5+5)).
That last point is what will help us solve this problem. Let's state the last point as an equation. For the purposes of crafting some nice tidy equations, I?? going to say that:
M=Mother?? age five years ago
D=Daughter?? age five years ago
The first equation is pretty simple:
M+D=40
We also have to write the part about the mother being 7 times older than the daughter into an equation:
M=7D
Now that we have two equations, we can use them together to solve the question about how old the mother and daughter were 5 years ago. First, we can get rid of M to make the equation easier to solve.
Since M=7D, substitute the M in the first equation with 7D in the second equation:
M+D=40  > 7D+D=40
Now solve for D.
7D+D=40
8D=40
8D/8=40/8
D=5
So 5 years ago, the daughter was 5 years old. Now extrapolate:
5 years ago the daughter was 5, so now she?? 10.
5 years ago, the mother was 7 times the age of her daughter (7D=M, or 7(5)=M), so 5 years ago the mother was 35, and now she?? 40 (7D+5=Mother?? current age, or 7(5)+5=Mother?? current age)
And if you need more proof,
40+10=50
```

#### Twin Brother Number-Math riddle

###### 49.Math Riddles

My twin brother lives at the reverse of my house number. The difference between our house numbers ends in two. What are the lowest possible numbers of our house numbers?

• `The lowest possible numbers for the houses are 19 and 91. The difference is 72.`

#### What is the pattern -Math riddle

###### 52.Math Riddles

One is to three as three is to five and five is to four and four is the magic number. What is the pattern?

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`Explanation :  One has three letters in the word three has five letters in it five has four letters and four has four letters in it (if you try more numbers they will always come back to the number four: so four is the magic number.`

#### Mrs.Jones and Apple Tree -Math riddle

###### 53.Math Riddles

Mrs Jones was very proud of her apple tree. One autumn, after harvesting her apples, she called her three sons together. ?Here are 150 apples,? she said. ?I want you to take them to the market tomorrow and sell them for me.? She gave Paul 15 apples, Nick 50, and Ben 85. ?Your job,? added Mrs Jones, ?is to sell the apples in such a way that each of you brings home the same amount of money.? How do they do it?

• `150 apples . `
`Explanation :  Paul 15 apples, Nick 50, and Ben 85.  sell the apples in such a way that each  brings home the same amount of money. To find :  How do they do it Solution: Let say Amount brought them by   = N Let say A , B & C are  the Prices at which they sell apples N = 15A N = 50B N = 85C N least value is LCM of  15 , 50  & 85 15  = 3 * 5 50 = 2 * 5 * 5 85 = 5 * 17 LCM = 2 * 3 * 5 * 5  * 17 LCM  = 2550 A = 170      B = 51      C = 30 Paul Sell apple at Rs 170 each Nick Sell Apple at Rs 51 Each Ben sell Apple at  Rs 30  Each They will Sell apple at price in Ratio 170 : 51  : 30  `

#### King Tut -Math riddle

###### 54.Math Riddles

King Tut died 120 years after King Eros was born. Their combined age when they died was 100 years. King Eros died in the year 40 B.C. In what year was King Tut born?

• `King Tut was born in 20 B.C. `
`Explanation :  There were 120 years between the birth of King Eros and the death of King Tut, but since their ages amounted to only 100 years, there must have been 20 years when neither existed. This would be a period between the death of King Eros, 40 B.C., and the birth of King Tut, 20 B.C.`

#### Three company-Math riddle

###### 56.Math Riddles

As we know 2 + 2 comes to the same as 2 x 2. Now find a set of three different whole numbers whose sum is equal to their total when multiplied.

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`Explanation :  The three different whole numbers whose sum is equal to their total when multiplied are 1, 2, and 3.`

#### Monkey is trying to climb a Coconut tree-Math riddle

###### 57.Math Riddles

A monkey is trying to climb a coconut tree. He takes 3 steps forward and slips back 2 steps downward. Each forward step is 30 cm and each backward step is 40cm. How many steps are required to climb a 100cm tree?

• `50`
`Explanation :  50 steps Each forward step= 30 cm  Each backward step = 40 cm  If monkey climbed 3 steps, means it covering 3?30=90 cm  If monkey slips 2 steps means = 2?40=80 cm then monkey covers only 10 cm.  Therefore for covering 10 cm monkey has to take 5 steps. Then for climbing 100 cm tree it takes  100?10= 10cm  For covering 100 cm it should take 5?10= 50 steps`

#### Minimum Apples-Math riddle

###### 58.Math Riddles

A carton contains some apples which were divided into two equal parts and sold to 2 traders Tarun and Tanmay. Tarun had two fruit shops and decided to sell an equal number of apples on both shops A and B respectively. Tanya visited shop A and bought all the apples in the shop for her kids. But one apple was left after dividing all the apples among her children. Each child got one apple, find the minimum number of apples in the carton?

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```Explanation :  Let the number of children be X Therefore, the number of apples bought by Tanya = ( X + 1) The total number of apples in the shop A = ( X + 1) Total number of apples bought by Trader Tarun =  2( X + 1 ) Total number of apples in the carton = 4( X + 1 ) Now, the minimum no of apples in a carton: We assume:  X is not equal to 0  X is not equal to 1 ( Tanya has children not a single child)  X  equal to 2  (Tanya has a minimum of 2 children) When X = 2Let the number of children be X
Therefore, the number of apples bought by Tanya = ( X + 1)
The total number of apples in the shop A = ( X + 1)
Total number of apples bought by Trader Tarun = 2( X + 1 )
Total number of apples in the carton = 4( X + 1 )
Now, minimum no of apples in carton:
We assume:
X is not equal to 0
X is not equal to 1 ( Tanya has children not a single child)
X equal to 2 (Tanya has a minimum of 2 children)
When X = 2
4( X + 1 )
= 4( 2 + 1 )
= 12
Thus, minimum of 12 apples
```

#### Tom And The Cartons-Math riddle

###### 59.Math Riddles

Tom is in charge of shipping and he can place 10 small boxes or 8 large boxes into a carton. A total of 96 boxes were sent in one shipment. The number of small boxes was less than large boxes. What is the total number of cartons he shipped?

• ```11 cartons.
```
`Explanation :  If a total of 96 boxes are shipped, then the large boxes in the cartons must be a multiple of 8, which means either 16 or 56 large boxes. Since there are more large boxes in the cartons than the small ones, the number of large boxes must be 56`

#### Zookeeper and the Animal's -Math riddle

###### 60.Math Riddles

If the zookeeper had 100 pairs of animals in her zoo and if two pairs of babies are born for each and every one of the original animals, and then sadly 23 animals don't survive, how many animals do you have left in total?

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`Explanation :  977 animals (100Ã—2 = 200; 200+800 = 1000; 1000-23 = 977)`