A telephone company needs to create a set of 3-digit area codes. The company is entitled to use only digits 2, 4
and 5, which can be repeated. If the product of the digits in the area code must be even, how many different
codes can be created?
26
Probability and combinations
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- manpsingh87
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_,_,_; now since each of the 3 blank spaces is to be filled either with 2,4,5 therefore there are total 3 ways for filling the each blank space, when no restriction is placed, then total no. of codes that can be generated will be 3*3*3=27;venmic wrote:A telephone company needs to create a set of 3-digit area codes. The company is entitled to use only digits 2, 4
and 5, which can be repeated. If the product of the digits in the area code must be even, how many different
codes can be created?
26
out of these 27 numbers, we have counted 1 odd number which will occur when all the digits will be odd, i.e.(555), so total no. of codes whose product is even= 27-1=26..!!!
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