3. What's the man's age?

A man is three times as old as his son. Five years later he will be two and a half times as old as his son.What's the man's age?

Answer: 
Age of the man = 45
Explanation:
Let the age of son & father be x & 3x.
After 5 yrs
son=x+5
father=3x+5
Also given,
2.5(x+5)=3x+5,
solving gives x=15.
fathers age=3x=45

2. Find the length of the wall.

If 20 men build a wall of length 56m in 6 days , what length of a similar wall can be build by 35 men in 3 days?

Answer: 
49m

1. Find the number.

What will be the 18th term in the following series?
0, 6, 6, 20, 20, 42,...?

Answer: 
342

Explanation: 
The series is of the form
(1*1)- 1
(2*2)+2
(3*3)- 3
(4*4)+ 4
(5*5)- 5
So the 18th term will be 
(18*18)+18=342.

Find the next letter

What is the next letter in this sequence OTTFFSS?

Answer: E

Explanation:
One
Two
Three
Four
Five
Six
Seven
Eight


So the intial of the letters is given,thefore answer is E

Find the no. of zeros.

A certain street has 1000 buildings. A sign maker is contracted to number the houses from 1 to 1000. How many zeros will he need?

Answer: 
192 zeros.

Age calculation

Rohit was 4 times as old as his son 8 years ago. After 8 years, Rohit will be twice as old as his son. What are their present ages?

Answer: 
Son's present age = 16 years
Rohit's present age = 40 years


Explanation:
Let son's age 8 years ago be x years. Then, Rohit's age 8 years ago = 4x years.
Son's age after 8 years = (x+8)+8 = (x+16) years.
Rohit's age after 8 years = (4x+8)+8 = (4x+16) years.
2(x+16) = (4x+16)  <=> 2x = 16 <=> x = 8.
Hence, son's present age = (x+8) = 16 years.
           Rohit's present age = (4x+8) = 40 years.

Find out the no. of words.

How many words can be formed by using all the letters of the word "DAUGHTER"
so that the vowels always come together?

Answer:
4320

Explanation:

Given word contains 8 different letters.When the vowels AUE are always together

We may suppose them to form an entity,treated as one letter.

Then,the letters to be arranged are DGHTR(AUE).

These 6 letters can be arranged in 6P6=6!=720 ways

The vowels in the group (AUE) may arranged in 3!=6 ways.

therefore Required number of words=(720 X 6)=4320.

Find the output.

void main()
{
static int i=5;
if(--i)
{
main();
printf("%d ",i);
}
}

Output: 
0 0 0 0


Explanation:
The variable 'i' is declared as static, hence memory for 'i' will be allocated
for only once, as it encounters the statement. The function main() will be called
recursively unless 'i' becomes equal to 0, and since main() is recursively called, so
the value of static 'i' ie., 0 will be printed every time the control is returned.

Find the missing no?

Look at this series: 4, 7, 25, 10, __, 20, 16, 19, ... What number should fill the blank?

Answer:

13

 

Explanation:

Two series alternate here, with every third number following a different pattern. In the main series, 3 is added to each number to arrive at the next. In the alternating series, 5 is subtracted from each number to arrive at the next.

What is the relation?

Introducing a boy, a girl said, "He is the son of the daughter of the father of my uncle." How is the boy related to the girl?

Answer:

Brother

Explanation:

The father of the boy's uncle → the grandfather of the boy and daughter of the grandfather → sister of father.