document.write( "Question 333347: How many integers greater than 20 and less than 30 are each the product of exactly two different numbers, both of which are prime?\r
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Algebra.Com's Answer #238859 by Edwin McCravy(20065)\"\" \"About 
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document.write( "21 = 3*7 and 3 and 7 are both prime.\r\n" );
document.write( "22 = 2*11 and 2 and 11 are both prime.\r\n" );
document.write( "23 = You might think of 1*23, but 1 is not prime.\r\n" );
document.write( "24 = 3*8 or 4*6, or 2*12, or 1*24, but none of \r\n" );
document.write( "     those is the product of 2 primes.\r\n" );
document.write( "25 = 5*5, 5 is prime but the two 5's are not different numbers.\r\n" );
document.write( "26 = 2*13 and 2 and 13 are both primes.\r\n" );
document.write( "27 = 3*9 but 9 is not prime.\r\n" );
document.write( "28 = 4*7 or 2*14 but neither is a product of two primes.\r\n" );
document.write( "29 = You might think of 1*29, but 1 is not prime.\r\n" );
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document.write( "So only 21, 22, 26  can be written as the product of two primes. \r\n" );
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document.write( "Therefore the answer is (D) Three\r\n" );
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document.write( "Edwin
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