document.write( "Question 847186: how many combinations using $1, $.50, $.20, $.10 to make $2.60 \n" ); document.write( "
Algebra.Com's Answer #510245 by swincher4391(1107)\"\" \"About 
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The answer is 558. Spoiler...there is a lot of work shown below. Please let me know if it becomes too confusing to follow. We first break the $1 into 3 cases, then from there we break the $.50 into 12 cases, then we break the $.20 from there into 70 cases, and then the $.10 is used to form 558 distinct cases. This could be achieved using a tree diagram. \r
\n" ); document.write( "\n" ); document.write( "Let's first find all possible numbers of each dollar that can be used to construct $2.60.\r
\n" ); document.write( "\n" ); document.write( "$1: We can have 0,1,or 2 dollars without exceeding $2.60\r
\n" ); document.write( "\n" ); document.write( "If 0 $1, then we have $2.60 that we must create without using dollars.
\n" ); document.write( "If 1 $1, then we have $1.60 that we must create without using dollars.
\n" ); document.write( "If 2 $1, then we have $.60 that we must create without using dollars.\r
\n" ); document.write( "\n" ); document.write( "We break into 3 subcases.\r
\n" ); document.write( "\n" ); document.write( "From $2.60 we can use 0,1,2,3,4,or 5 $.50
\n" ); document.write( "From $1.60 we can use 0,1,2,or 3 $.50
\n" ); document.write( "From $.60 we can use 0 or 1 $.50\r
\n" ); document.write( "\n" ); document.write( "Now we've broken into 12 subcases.\r
\n" ); document.write( "\n" ); document.write( "From $2.60 we can use 0 - 13 $.20 (14 subcases)
\n" ); document.write( "From $2.10 we can use 0 - 10 $.20 (11)
\n" ); document.write( "From $1.60 we can use 0 - 8 $.20 (9)
\n" ); document.write( "From $1.10 we can use 0 - 5 $.20 (6)
\n" ); document.write( "From $.60 we can use 0 - 3 $.20 (4)
\n" ); document.write( "From $.10 we can use 0 $.20 (1)\r
\n" ); document.write( "\n" ); document.write( "From $1.60 we can use 0 - 8 $.20 (9)
\n" ); document.write( "From $1.10 we can use 0 - 5 $.20 (6)
\n" ); document.write( "From $.60 we can use 0 - 3 $.20 (4)
\n" ); document.write( "From $.10 we can use 0 $.20 (1)\r
\n" ); document.write( "\n" ); document.write( "From $.60 we can use 0 - 3 $.20 (4)
\n" ); document.write( "From $.10 we can use 0 $.20 (1)\r
\n" ); document.write( "\n" ); document.write( "Now we have 70 subcases (don't worry this is the last time)\r
\n" ); document.write( "\n" ); document.write( "From $2.60 we have 26 subcases
\n" ); document.write( "From $2.40 we have 24 subcases
\n" ); document.write( "From $2.20 we have 22
\n" ); document.write( "From $2.00 we have 20
\n" ); document.write( "From $1.80 we have 18
\n" ); document.write( "From $1.60 we have 16
\n" ); document.write( "From $1.40 we have 14
\n" ); document.write( "From $1.20 we have 12
\n" ); document.write( "From $1.00 we have 10
\n" ); document.write( "From $0.80 we have 8
\n" ); document.write( "From $0.60 we have 6
\n" ); document.write( "From $0.40 we have 4
\n" ); document.write( "From $0.20 we have 2
\n" ); document.write( "From $0.00 we have 0\r
\n" ); document.write( "\n" ); document.write( "From $2.10 we have 21
\n" ); document.write( "19
\n" ); document.write( "17
\n" ); document.write( "15
\n" ); document.write( "13
\n" ); document.write( "11
\n" ); document.write( "9
\n" ); document.write( "7
\n" ); document.write( "5
\n" ); document.write( "3
\n" ); document.write( "1\r
\n" ); document.write( "\n" ); document.write( "16
\n" ); document.write( "14
\n" ); document.write( "12
\n" ); document.write( "10
\n" ); document.write( "8
\n" ); document.write( "6
\n" ); document.write( "4
\n" ); document.write( "2
\n" ); document.write( "0\r
\n" ); document.write( "\n" ); document.write( "11
\n" ); document.write( "9
\n" ); document.write( "7
\n" ); document.write( "5
\n" ); document.write( "3
\n" ); document.write( "1\r
\n" ); document.write( "\n" ); document.write( "6
\n" ); document.write( "4
\n" ); document.write( "2
\n" ); document.write( "0\r
\n" ); document.write( "\n" ); document.write( "1\r
\n" ); document.write( "\n" ); document.write( "16
\n" ); document.write( "14
\n" ); document.write( "12
\n" ); document.write( "10
\n" ); document.write( "8
\n" ); document.write( "6
\n" ); document.write( "4
\n" ); document.write( "2
\n" ); document.write( "0\r
\n" ); document.write( "\n" ); document.write( "11
\n" ); document.write( "9
\n" ); document.write( "7
\n" ); document.write( "5
\n" ); document.write( "3
\n" ); document.write( "1\r
\n" ); document.write( "\n" ); document.write( "6
\n" ); document.write( "4
\n" ); document.write( "2
\n" ); document.write( "0\r
\n" ); document.write( "\n" ); document.write( "1\r
\n" ); document.write( "\n" ); document.write( "6
\n" ); document.write( "4
\n" ); document.write( "2
\n" ); document.write( "0\r
\n" ); document.write( "\n" ); document.write( "1\r
\n" ); document.write( "\n" ); document.write( "Adding this all together gives us 558.\r
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