Question 595797: The access code for a car's security system consists of four digits. The first digit cannot be 5 and the last digit must be even or zero. How many different codes are available?
Found 2 solutions by stanbon, jerryguo41:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! The access code for a car's security system consists of four digits. The first digit cannot be 5 and the last digit must be even or zero. How many different codes are available?
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Pattern: DDDD
1st: 9 ways
2nd: 10 ways
3rd: 10 ways
4th: 5 ways
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Total codes: 9*5*100 = 4500
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Cheers,
Stan H.
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Answer by jerryguo41(197)  (Show Source):
You can put this solution on YOUR website! Code:
1st Number: 1, 2, 3, 4, 6, 7, 8, 9, 0 (9 possible combos)
2nd Number: 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 (10 possible combos)
3rd Number: 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 (10 possible combos)
4th Number: 1, 3, 5, 7, 9 (5 possible combos)
So to calculate number of codes:
Possible numbers of (1st Number*2nd Number*3rd Number*4th Number)
There are 4500 different possible combinations
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