document.write( "Question 254471: What is the last digit of the product you obtain by multiplying the first 2002 odd
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Algebra.Com's Answer #186887 by solver91311(24713) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "The odd primes are all of the primes except for 2. 5 is the third prime number and the second odd prime number, and is therefore a factor of the product of the first 2002 odd prime numbers. The product of 5 and any odd number ends in 5. The product of any two odd numbers is odd, so the product of the first odd prime number, namely 3 times the product of the 2000 prime numbers subsequent to 5 must be odd. The product of that number and 5 is the product of the first 2002 odd primes, and it must end in 5.\r
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\n" ); document.write( "\n" ); document.write( "Super double plus extra-credit: What is the last digit of the first 1583 primes?\r
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