document.write( "Question 978179: My age this year is a multiple of 8.Next year it will be a multiple of 7.How old am i? \n" ); document.write( "
Algebra.Com's Answer #599646 by KMST(5328)\"\" \"About 
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TRIAL AND ERROR:
\n" ); document.write( "the current age is a multiple of 8, so we try different multiples of 8.
\n" ); document.write( "We can make a table with reasonable ages that are multiples of 8,
\n" ); document.write( "and see if the age next year (age+1) would be a multiple of 7.
\n" ); document.write( "
\n" ); document.write( "The age of that person should be \"highlight%2848%29\" this year, and will be \"49\" at some time next year.
\n" ); document.write( "A person could be \"104\" and expect to have another birthday next year,
\n" ); document.write( "but it is very rare to be that old,
\n" ); document.write( "and someone that old would probably not be asking math question like that one.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "MAKING IT LOOK MORE LIKE ALGEBRA:
\n" ); document.write( "\"8n\"= age this year (for some number \"n\" that is a positive integer).
\n" ); document.write( "\"8n%2B1=7p\"= age next year (for some number \"p\" that is a positive integer).
\n" ); document.write( "Let us get some useful relationship from that:
\n" ); document.write( "\"8n%2B1=7p\"
\n" ); document.write( "\"7n%2Bn%2B1=7p\"
\n" ); document.write( "\"n%2B1=7p-7n\"
\n" ); document.write( "\"n%2B1=7%28p-n%29\"
\n" ); document.write( "We know that \"n%2B1\" is a positive integer, so \"p-n\" must be a positive integer too.
\n" ); document.write( "\"p-n=1\" gives us \"n%2B1=7\"--->\"n=7-1\"--->\"n=6\" and since \"age=8n\" ,
\n" ); document.write( "\"system%28age=8n%2Cn=6%29\"--->\"system%28age=8n%2C8n=8%2A6%29\"--->\"highlight%28age=48%29\"
\n" ); document.write( "\"p-n%3E=2\" gives us \"n%2B1%3E=14\"--->\"n%3E=14-1\"--->\"n%3E=13\" and since \"age=8n\" ,
\n" ); document.write( "\"system%28age=8n%2Cn%3E=13%29\"--->\"system%28age=8n%2C8n%3E=8%2A13%29\"--->\"age%3E=104\" ,
\n" ); document.write( "which not a very reasonable answer, as it is unlikely to reach age 104
\n" ); document.write( "while expecting to live until the next year and the next birthday,
\n" ); document.write( "and asking this kind of math question.
\n" ); document.write( "However, if I am in good physical and mental health 40 years from now,
\n" ); document.write( "I will post the same question and cackle with glee.\r
\n" ); document.write( "\n" ); document.write( "FOR A TRICK QUESTION
\n" ); document.write( "I do not think it is meant to be a trick question, so I would answer the answer above.
\n" ); document.write( "For a trick question,
\n" ); document.write( "that person could have had a birthday and turned \"56\" earlier this yea.
\n" ); document.write( "So, at the beginning of next year would still be \"56\" (until the next birthday.
\n" ); document.write( "As \"56=8%2A7\" is a multiple of \"8\" and a multiple of \"8\" ,
\n" ); document.write( "that person's age would be \"56\"= a multiple of \"8\" now,
\n" ); document.write( "and \"56\"= a multiple of \"7\" for some time next year,
\n" ); document.write( "at the beginning of the year, before the next birthday,
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