Given digits 2,2,3,3,3,4,4,4,4 how many distinct 4 digit numbers greater than 3000 can be formed?

options

a-50

b-51

c-52

d-54

plz give details ..........its a general aptitute question

Relevance
• 1 decade ago

what do you mean, is that all 4 digits are distinct?

• 3 years ago

3 And 4 Digit

• Awms A
Lv 7

First digit is either 3 or 4. We'll consider each case separately:

(1) First digit is 3:

Then the rest of the numbers must come from the list: 2, 2, 3, 3, 4, 4, 4, 4

Therefore we may choose any 3-digit sequence except 222 and 333 for the rest of the digits. This shows there are

3*3*3 - 2 = 25

numbers in this case.

(2) First digit is 4:

Then the rest of the numbers must come from the list 2, 2, 3, 3, 3, 4, 4, 4

Therefore we may choose any 3-digit sequence except 222 for the rest of the digits. This shows there are

3*3*3 - 1 = 26

numbers in this case.

Now, the total number is just 25 + 26 = 51.

• 6 years agoReport

Can you explain why you haven't taken the numbers 3222 ,3333 and 4222
why they are ignored ? because they are not being repeated and are distinct