document.write( "Question 1110439: Jack and Jill spent two weeks touring Boston, New York City, Philadelphia, and Washington D.C. They paid $120,$200,$80, and $100 per night respectively. Their total bill was $2020. The number of days spent in NYC was the same as the sum of the days spent in Boston and D.C. They spent three times as many days in NYC as they did in Philly. How many days did they stay in each city?
\n" ); document.write( "a) answer question using a combination of algebra and logic.
\n" ); document.write( "b) answer the question again using a 4x4 system of equations.\r
\n" ); document.write( "\n" ); document.write( "Does this mean there's another way to do this without a system of equations? That's the only way I can think of doing it. I just know that 120B+200N+80P+100W=2020.
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Algebra.Com's Answer #725556 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Jack and Jill spent two weeks touring Boston, New York City, Philadelphia, and Washington D.C.
\n" ); document.write( "let b, n, p, and w = the no. of days in each season, write an equation for each statement
\n" ); document.write( ":
\n" ); document.write( " They paid $120,$200,$80, and $100 per night respectively.
\n" ); document.write( " Their total bill was $2020.
\n" ); document.write( "120b + 200n + 80p + 100w = 2020
\n" ); document.write( "Simplify, divide by 20
\n" ); document.write( "6b + 10n + 4p + 5w = 201
\n" ); document.write( ":
\n" ); document.write( " The number of days spent in NYC was the same as the sum of the days spent in Boston and D.C.
\n" ); document.write( "n = b + w
\n" ); document.write( "or
\n" ); document.write( "b = n - w
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\n" ); document.write( " They spent three times as many days in NYC as they did in Philly.
\n" ); document.write( "n = 3p
\n" ); document.write( "or
\n" ); document.write( "p = \"n%2F3\"
\n" ); document.write( ":
\n" ); document.write( "a) answer question using a combination of algebra and logic.
\n" ); document.write( "Substitute in the 1st equation, for b & p
\n" ); document.write( "6(n-w) + 10n + 4(\"n%2F3\" + 5w = 101
\n" ); document.write( "get rid of the fraction, multiply thru b 3
\n" ); document.write( "18(n-w) + 30n + 4n + 15w = 303
\n" ); document.write( "18n - 18w + 30n + 4n + 15w = 303
\n" ); document.write( "combine like terms
\n" ); document.write( "52n - 3w = 303
\n" ); document.write( "have 4 unknowns and only 3 equations, but we know they have to be integers
\n" ); document.write( "Write an equation we can enter into a graphing calc
\n" ); document.write( "3w = 52n - 303
\n" ); document.write( "w = \"%2852n-303%29%2F3\"
\n" ); document.write( "w = \"52%2F3\"n - 101
\n" ); document.write( "table reveals only one integer solution that makes sense
\n" ); document.write( "n = 6, w = 3
\n" ); document.write( "therefore
\n" ); document.write( "p = 6/3 = 2 days
\n" ); document.write( "b = 6 - 3 = 3 days
\n" ); document.write( ":
\n" ); document.write( "How many days did they stay in each city?
\n" ); document.write( "Boston 3 days, New York 6 days, Philly 2 days and Wash 3 days
\n" ); document.write( "see if that works
\n" ); document.write( "120(3) + 200(6) + 2(80) + 100(3) = 2020
\n" ); document.write( ":
\n" ); document.write( " b) answer the question again using a 4x4 system of equations.
\n" ); document.write( "I don't know either, how you could do this with a 4 by 4 matrix
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