How many 4-digit positive integers are there in which all 4 digits are even?
A. 625
B. 600
C. 500
D. 400
E. 256
oa c
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4-digit positive integers
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sudhir3127
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C 500ska7945 wrote:How many 4-digit positive integers are there in which all 4 digits are even?
A. 625
B. 600
C. 500
D. 400
E. 256
oa c
to be an even number we have to take into consideration only 0,2,4,6,8
first digit can be formed in 4 ways( cant take 0 )
next 3 digits out of 5 in 5^3 ways
thus its
4*5^3 = 500
hope it helps..
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carefreeamit
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4 digit number means it should be >= 1000 and <= 9999.
The first place can be taken by 2,4,6,8 i.e. in 4 ways.
The second, third & fourth place can be taken by 0,2,4,6,8 i.e. 5 ways each.
So the number of positive integers will be = 4*5*5*5 = 500
Ans C.
The first place can be taken by 2,4,6,8 i.e. in 4 ways.
The second, third & fourth place can be taken by 0,2,4,6,8 i.e. 5 ways each.
So the number of positive integers will be = 4*5*5*5 = 500
Ans C.
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Scott@TargetTestPrep
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Solution:
The even digits are 0, 2, 4, 6, and 8. However, since the first digit (or the thousands place digit) can’t be 0, there are 4 choices for the thousands digit, while the other three places (hundreds, tens, and units) have 5 choices each. Therefore, the total number of 4-digit numbers with all even digits is 4 x 5 x 5 x 5 = 500.
Answer: C
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