Latest CTS Aptitude Question SOLUTION: In all four digit numbers(i.e) from 1000 to 9999. How many times the number 2 is used?

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

CTS Question Papers: CTS Interview Experience(3) CTS Company Profile

(#M40153649) CTS Numerical Ability question Number System Keep an EYE

In all four digit numbers(i.e) from 1000 to 9999. How many times the number 2 is used?

Asked In CTS Animesh Gupta (9 years ago)

Unsolved Read Solution (6)

Is this Puzzle helpful?   (5)   (6) Submit Your Solution Number System

Read Solution (6) :

anandhi  (9 years ago)

If you fix 2 in units place, the remaining places can be filled in 9, 10, 10 ways. We can only fill the left most place only in 9 ways because 0 cannot be used. So
Units place: 9*10*10*1=900
Tens place: 9*10*1*10=900
Hundreds place: 9*1*10*10=900
Thousands place:1*10*10*10=1000

Total: 900+900+900+1000=3700

Is this solution Helpfull? Yes (23) | No (2)  

parth  (9 years ago)

In 100 it comes 21 times then in 10000 2100 times + 100 *10 for 200,201,202,...299
Total 2100+1000=3100

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

parth  (9 years ago)

In 100 it comes 20 times 2 12 32...92 =9
20 21 22 23 ...29 =11 total 11+9= 20
In 1000 it comes 20*10=200
In 9000 it comes 200*9=1800
200..299 100 times
100*9=900
2000..2999 1000 times
Total=1000+900+1800=3700

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

shuja siddiqui  (9 years ago)

total 4 digit numbers that we can form is 9*10*10*10=9000
total 4 digit numbers that we can form without using 2 is 8*9*9*9=5832
so 4 digit no. with 2
9000-5832=3168

Is this solution Helpfull? Yes (3) | No (1)  

SANTOSH RAY  (9 years ago)

confuse mat karo bhai sbko@ parth

Is this solution Helpfull? Yes | No   

kamatchi  (9 years ago)

Explain it...

Is this solution Helpfull? Yes | No   

Please Login to Read Solution.