document.write( "Question 11253: My son homework is on proportions. Example: \r
\n" ); document.write( "\n" ); document.write( "If 2 adults are needed for every 15 students, how many students are needed for 180 students?\r
\n" ); document.write( "\n" ); document.write( "2 ?
\n" ); document.write( "- = -
\n" ); document.write( "15 180\r
\n" ); document.write( "\n" ); document.write( "15? = 360
\n" ); document.write( "? = 24\r
\n" ); document.write( "\n" ); document.write( "First of all, can't I reduce...cancel out the 2 for a 1 and the 180 for 90. If I do then the number changes. Am I suppose to cancel out numbers? Why/why not? \n" ); document.write( "

Algebra.Com's Answer #5851 by kyle491(5) $\"\"$ $\"About$

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When setting up proportions you first need to set up what you know and what you dont. \r
\n" ); document.write( "\n" ); document.write( "You know that 2 adults are needed for 15 students so start setting up the proportion as: 2 over 15\r
\n" ); document.write( "\n" ); document.write( "Now you need to find out what you dont know: how many adults are needed for 180 students. So set up the proportion like you started to, putting the adults to students. You should have 2 over 15 equals X over 180.
\n" ); document.write( " \r
\n" ); document.write( "\n" ); document.write( "Now we need to start the math. First cross mulitply the two numbers that you are able to, which are 2 and 180. You should come up with 360. Now, you divide 360 by the lonely number, 15. You should get X=12. 12 teachers are needed.\r
\n" ); document.write( "\n" ); document.write( "When doing proportions always remember to set up what you already know to what you need to know. \n" ); document.write( "

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