📄 puzzles.html
字号:
i.e; S + 4 + 3 + 4 + S + 0 = 9n
The only digit that meets these two condition is 8
35.HEIGHT OF A ROOM
Given the floor area of a room as 24 feet by 48 feet,and the space
diagonal of the room as 56 feet,Can you find the height of the room?
Solution:
We know that,
Volume of a cube =l pow(2) + b pow(2) + h pow(2).
Here the values of l & b are given.
We also know that
(diagonal)pow(2) = (length)pow(2) + (breadth)pow(2).
=> (x)pow(2) = 24 pow(2) + 48 pow(2)
=> x = 24squareroot(5);
Therefore,volume= h pow(2) + x pow(2) =56 pow(2)
=> h=16
Therefore,height of the room=16 ft.
36.A QUESTION OF DISTANCE
It was a beautiful sunny morning. The air was fresh and a mild wind
was blowing against my wind screen I was driving from Banglore to
Brindavan Gardens. It took me 1 hour and 30 miutes to complete
the journey. After lunch I returned to Banglore. I drove for
90 minutes.How do you explain it?
Solution:
90 minutes = 1 hour 30 minutes.
Hence,the driving time there and back is absolutely the same because
90 minutes and 1 hour and 30 minutes are one and the samething.
37.ARRANGE THE DIGITS:
Arrange the digits 1,2,3,4,5,6,7,8,9 in order from left to right
and use only + or _ signs so as to produce a result of 100?
Sol:
123-45-67+89
<font size=3> <a href="puzzles.html"><b>Top</b></a></font>
38.DIVISION OF 45:
Can you divide the number 45 into four parts such that when 2 is
added to the first part, 2 is subtracted from the second part, 2 is
multiplied by the third part, and the fourth part is divided by 2.
All the four results to be the same number.
Sol:
Let us take A,B,C,D are the four equal parts and their sum is
equal to 45.
A+B+C+D = 45
Given that,
A+2 = B-2 = C*2 = D/2 ----------------(1)
=>A = B-4 ; C = (B-2)/2 ; D = 2(B-2)
=>B-4 + [(B-2)/2] + 2(B-2) = 45
=>B=12
:. A=8 , C=5 , D=20
And condition (1) is satisfied.
i .e; 8+2 = 12-2 = 5*2 = 20/2
39.SPECIAL NUMBER:
What is the special about the number 1729?
Sol:
This is popularly known as Ramanujan's number. This is the known
number that is a sum of two cubes in two different ways.
i .e; (10*10*10) + (9*9*9) = 1729
( 12*12*12) + (1*1*1) = 1729
40.PRICE OF A BOTTLE:
A bottle and its cork together cost Rs 1.10, and the bottle
costs Rs 1.00 more than its cork. What is the price of the bottle?
Sol:
Let us assume that,
B = Price of the bottle
C = Price of the cork
It is given that,
B + C = Rs 1.10 -------------------(1)
and B – C = Rs 1.00 -------------------(2)
From the equations (1) and (2) it is clear that
B = Rs 1.05
C = Rs 0.05
41.A QUESTION OF DISTANCE:
It was a beautiful sunny morning. The air was fresh and a mild wind
was blowing against my wind screen. I was driving from Banglore to
Brindavan Gardens. It took me one hour and 30 minutes to complete
the journey. After lunch I returned to banglore. I drove for
90 minutes. How do you explain it?
Sol:
90 minutes = 1 hour 30 minutes.
Hence, the driving time there and back is absolutely same because
90 minutes and 1 hour 30 minutes are one and the same.
42.FOR THE CHARITIES:
One day when I was walking on the road in New Delhi, a group of boys
approached me for donation for their poor boys' fund. I gave them a
Rupee more than half the money I had in my purse. I must have walked
a few more yards when a group of women approached me for donation,
for an orphanage. I gave them 2 Rupees more than half the money I
had in my purse. Then after a few yards I was approached by a
religious group for a donation to the temple they were building.
I gave them 3 Rupees more than half of what I had in my purse.
At last I returned to my hotel room, I found that I had only one
Rupee remaining in my purse. How much money did I have in my purse
when I started?
Sol:
Suppose that the money in his purse when he started = x --------(1)
For poor boys fund he gave x/2 + 1 Rs/- -----------------(2)
i .e; 1 Rupee more than half the amount he had.
Now he left with [x - (x/2 + 1)] =(x-2)/2 Rs/-
For Orphanage he gave [(x/2 – 1)/2] +2 = (x+6)/4 Rs/- -----(3)
Now he left with [(x-2)/2] – [(x+6)/4] = (x-10)/4 Rs/-
For temple building he gave [(x-10)/4]/2 + 3 = (x+14)/8 Rs/- ---(4)
Now he left with [(x-10)/4] – [(x+14)/8] = (x-34)/8 Rs/-
Finally he had 1 Rupee in his purse.
i .e; Actual amount – Expended amount = 1
:. from (1),(2),(3) and (4) we have
x-{ [ (x+2)/2 ] + [ (x+6)/4 ] + [ (x+14)/8 ] } = 1
=>x-34=8
=> x=42
:. The original amount in his purse at the beginning = Rs 42/-
43.A PAIR OF PALLINDROMES
Multiply 21978 by 4.Comment about the result?
Solution:
21978*4=87912.
If we clearly observe the two numbers 21978 and 87912, the resultant
number ie; 87912 is the reverse number of the number 219780.
There fore these two numbers are a pair of paindromes.
44.A COMPUTING PROBLEM
Compute: [5-2/(4-5)]pow(2).
Solution:
[5-2/(4-5)]pow(2)
=[5-2/(-1)]pow(2)
=[5+2]pow(2)=49.
45.CONTINUE THE SERIES
1,3,6,10.Name the next three numbers in the series.
Solution:
The series is +2,+3,+4,-----------------
There fore next three numbers are:
10+5,10+5+6,10+5+6+7 = 15,21,28.
46.NAME FIVE TERMS OF ANOTHER SERIES
These are the numbers that are the first five terms of a series that
add upto 150.Can you name five terms of another series without
fractons that add upto 153?
[ex: 10,20,30,40,50. sum=150.]
Solution:
Each term in this series is a factorial, in other words,the product
of a the numbers from 1 to that particular term considered.
The first five terms of the series are,there fore 1,2,6,24,120.
Their sum is 153 and are factorials of 1,2,3,4,5 respectively.
47.FIND OUT THE TIME
What does 1408 hours mean?
Solution:
1408 hours is actually 8 minutes past 2 PM.
This is the system of twenty-four-hour cock.Writing the hours and
minutes this way is a sensible means of avoiding confusion
between AM and PM.
48.FIND OUT TTHE PATTERN
What do you think the pattern is?6,24,60,120,210,336,………………
Solution:
The series is 1.2.3, 2.3.4, 3.4.5, 4.5.6, 5.6.7, 6.7.8,----------
The next numbers would be 7.8.9, 8.9.10,-------
(or) 504, 720,-----------------------
<font size=3> <a href="puzzles.html"><b>Top</b></a></font>
49.THE TRAIN AND THE CYCLIST
A railway track runs parallel to a road until a bend brings the road
to a level crossing. A cyclist rides along to work along the road
every day at a constant speed of 12 miles per hour.
He normally meets a train that travels in the same direction at the
crossing One day he was late by 25 minutes and met the train 6 miles
ahead of the level crossing. Can you figure out the speed of the train?
Solution:
Suppose that the train and the cyclist meet everyday at the crossing
at 8:00A.M. i. e; starts at 7:00A.M
Since the cyclist is late by 25 minutes, he starts at 7:25A.M
As his speed is 12 miles per hour, he reaches the crossing at
7:25A.M + 1 Hour = 8:25A.M
By 8:30A.M the train is 6 miles ahead of the cyclist
The difference between their timings = 8:30A.M – 8:25A.M = 5 Minutes
The difference between their distances = 6 Miles
Therefore,the train travels 6 miles in 5 minutes
In 1 minute it travels ---------------------?
= [(1 * 6) /5] * 60
= 72 Miles/hour
50.HEIGHT OF THE PALM TREE
A palm tree was 90 cm high, when it was planted. It grows by an equal
number of cm each year, and at the end of the seventh year it was one
ninth taller than at the end of the sixth year. Can you tell how tall
was the tree at the end of the twelfth year?
Solution:
Suppose that the tree grows x cm each year
Height of the tree at the end of the sixth year = (90 + 6x) cm
Growth in seventh year is,
X = 1/9(90 + 6x) cm
x = 10 + 2x/3
x = 30
Therefore the height of the tree at the end of the twelfth
year=(90+12*30)=450cm
51.PROBLEM OF AGE
Recently I attended a cocktail party. There was a beautiful young lady,
who seemed very vitty and intelligent. She was posed a question, “
how old are you? â€. She answered , “ my age 3 years hence
munltiply by 3 and from that subtracted 3 times my age 3 years ago will
give you my exact age? How od is the lady?
Solution:
Let the age be x
Age after 3 years wi be (x + 3)
Age before 3 years = (x – 3)
Hence 3(x + 3) – 3(x – 3) = x
x = 3x + 9 – 3x + 9
x = 18
Therefore the age of the lady = 18 years
52.CONSECUTIVE NATURASL NUMBERS
There are two consecutive natural numbers whose product is equal to the
product of three consecutive natural numbers,for example
x(x+1) = y(y+1)(y+2).What are the two numbers?
Solution:
14 * 15 = 5 * 6 * 7
53.SOME GLUTTON
A man sitting beside me at a hotel ate idlis one after the other by
ordering plate by plate. He said to me after drinking some water the
last one I ate was my hundredth idli in last five days. Each day
I ate 6 more than the previous day. Can you tell me how many he
ate yesterday?
Soluton:
First day the number of idlis he ate be x
Second day the count is (x+6)
Third day ------------------------- (x+12)
Fourth day ------------------------(x+18)
Fifth day ---------------------------(x+24)
Total is 5x + 6(1+2+3+4) =100
5x + 60 =100
x = 8
Day Idlis
1 8
2 14
3 20
4 26
5 32
So, on fourth day the number of idlis the man ate were 26.
</font>
<font size="3" style="URL Chancery">
<a href="manual.html">Back</a> <a href="puzzles.html">Top</a>
<a href="../Index.html">Back To Main</a>
</font>
</pre>
<!--End data -->
</font>
</td>
</tr>
</table>
<font face="Verdana, Arial, Helvetica, sans-serif" size="2"><font face="Verdana, Arial, Helvetica, sans-serif" size="2"><font face="Arial,Helvetica,sans-serif"><font size="2" color="#FFFFFF"><a href="http://www.WorldBest.com/" target="_top">
</a></font></font></font></font>
<!-- #EndLibraryItem --></div>
</div>
</td>
<td width="3%" bgcolor="#919EB4" valign="top">
</td>
</tr>
</table>
</div>
</td>
<td width="66" bgcolor="#396699" valign="top" align="center">
</td>
</tr>
<tr bgcolor="#396699">
<td width="66" height="2" align="left" valign="bottom">
<img src="../leftb.gif" width="60" height="66" ></td>
<td valign="top" bgcolor="#396699" height="2" width="570" align="center">
<font face="helvetic" size="3" color="ffff66">
<div align=right> Contact: 040-23000700 </div>
</td>
<td align="right" bgcolor="#396699" valign="bottom">
<img src="../rightb.gif" width="66" height="60" ></td>
</tr>
</table>
</body>
</html>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -