HP Placement Paper II

HP Placement Paper 2011 @ Bangalore

1) In a hotel, rooms are numbered from 101 to 550. A room is chosen at random. What is the probability that room number starts with 1, 2 or 3 and ends with 4, 5 or 6?
Answer
There are total 450 rooms.
Out of which 299 room number starts with either 1, 2 or 3. (as room number 100
is not there) Now out of those 299 rooms only 90 room numbers end with 4, 5 or
6.So the probability is 90/450 i.e. 1/5 or 0.20.
 

2) What is the four-digit number in which the first digit is 1/3 of the second, the third is the sum of the first and second, and the last is three times the second?
Answer
The 4 digit number is 1349.
 

HP Placement Paper I

HP Placement Paper 2011 @ Chennai

1) If one-seventh of a number exceeds its eleventh part by 100 then the number is…
(i) 770
(ii) 1100
(iii) 1825
(iv) 1925
Solution:
Let the number be x. Then X/7 – x/11 =100 11x-7x = 7700 x=1925.
 

2) The ratio of Rita’s age to her mother’s age is 3:8. The difference of their ages is 35 years. The ratio of their ages after 4 years will be:
(i) 7:12
(ii) 5:12
(iii) 38:43
(iv) 42:47
Solution:
Let their ages be 3x and 8x
8x – 3x =35
x =7
Their present ages are 21 and 56 years.
Ratio of their ages after 4 years are 25:60 = 5:12