Latest TCS Aptitude Question SOLUTION: The citizens of planet Oz are 4 fingured and thus have developed a number system in base 4. A certain street i n Oz contains 100 buildings bumberred from 1 to 100. How many 2's are

• Placement Papers
• /
• TCS
• /
• Numerical Ability
• /
• Number System

TCS Question Papers: TCS Interview Experience(90) TCS Company Profile

(#M40002367) TCS Numerical Ability question Keep an EYE

The citizens of planet Oz are 4 fingured and thus have developed a number system in base 4. A certain street i n Oz contains 100 buildings bumberred from 1 to 100. How many 2's are used in numbering these buildings? Express your answer in base 10.

Asked In TCS Aniket (12 years ago)

Unsolved Read Solution (10)

Is this Puzzle helpful?   (18)   (4) Submit Your Solution Number System

Read Solution (10) :

Subhash Yadav  (12 years ago)

ANS:8
EXP:
no of any digit used from 1 to 100=2*B
thus no of 2=2*4
=8

Is this solution Helpfull? Yes (23) | No (5)  

gayathri padma  (12 years ago)

ans is 8.
in the question they have mentioned it as "base 4", so we should take numbers from from 0 to 4, so take the number series as:
0,1,2,3,4,
11,12,13,14,
21,22,23,24,
31,32,33,34,
41,42,43,44, hence in abv series ter are 8 2s.
(since the base is 4 consider the number series only till 40's.
if base 8 then consider till 80's and so on........)
or the question can also be solved by using formula.... 2*n ==> 2*4=8.

Is this solution Helpfull? Yes (8) | No (6)  

sonia   (12 years ago)

2
houses r numbered 1-100..
first2 will come frm 0-9
2nd 2 in 12
then 10 2in twenty series
3 rd in 32
likewise when we count all 2 ans is 20
evrything else is to confuse u

Is this solution Helpfull? Yes (5) | No (8)  

karthik  (12 years ago)

number of 2'S between 1 to 10 =1
number of 2'S between 11 to 20=2
number of 2'S between 21 to 30=4
number of 2'S between 31 to 100=1
number of 2's=8

Is this solution Helpfull? Yes (3) | No (5)  

gvravi  (12 years ago)

basically no. of 2's from 1 to 100 are 2,12,20,21,22,23,24,25,26,27,28,29,32,42,52,62,72,82,92 i.e 20.
by converting this 20 into base(10) whatever he will give, that will be the answer.

Is this solution Helpfull? Yes (2) | No (2)  

phani  (12 years ago)

ans is 9... 2,12,21,22,23,24,32,42...22 is having two twos...

Is this solution Helpfull? Yes (2) | No (4)  

priya malik  (12 years ago)

in this type of question apply this rule...
no.of any digit within 0-100=20;
so no. of 2's=20
number system is in base 4
so=2*(4^0)+ 0*(4^0)=8

Is this solution Helpfull? Yes (2) | No (5)  

bhupendra  (12 years ago)

20 because 2 occur 20 times in 100

Is this solution Helpfull? Yes (1) | No (5)  

anwesha ghosh  (12 years ago)

the 2s are.....2,12,20,21,22,23,32 so number of 2 in decimal=8

Is this solution Helpfull? Yes (1) | No (1)  

Sourav Ghosh  (12 years ago)

Ans. 8

(4^2- 3^2) numbers contain 2. there is 22 also. total 2s= 6+2=8

Is this solution Helpfull? Yes | No (7)  

Please Login to Read Solution.