document.write( "Question 830708: please show me how to use unit multipliers to convert 300 min to hr \n" ); document.write( "
Algebra.Com's Answer #500805 by Edwin McCravy(20056) $\"\"$ $\"About$
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document.write( "A UNIT MULTIPLIER is a special kind of FRACTION.  Here are three\r\n" );
document.write( "things you need to know about fractions in order to make unit \r\n" );
document.write( "multipliers and use them to change from one unit to another:: \r\n" );
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document.write( "1. You know that when you multiply a fraction by 1, you don't\r\n" );
document.write( "   change its value.\r\n" );
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document.write( "2. You know that any fraction whose numerator is the same as\r\n" );
document.write( "   its denominator is equal to 1.\r\n" );
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document.write( "3. You know that when you multiply fractions, if there is a numerator\r\n" );
document.write( "   factor and a denominator factor that are the same, you can cancel \r\n" );
document.write( "   them out.\r\n" );
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document.write( "4. Unit multipliers are special kinds of fractions that equal\r\n" );
document.write( "   to one.\r\n" );
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document.write( "To make a unit multiplier you need to know a conversion fact.\r\n" );
document.write( "We know the conversion fact:  60 minutes = 1 hour.\r\n" );
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document.write( "There are two unit multiplier (fractions) you can make with \r\n" );
document.write( "\"60 minutes = 1 hour\"\r\n" );
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document.write( "These two unit multipliers are  and \r\n" );
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document.write( "They both have value 1.  That's because their numerator and denominator \r\n" );
document.write( "are equal in size.  They don't look the same but we know they are the\r\n" );
document.write( "same, because 60 minutes and 1 hour are the same.\r\n" );
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document.write( "Now let's do the problem.\r\n" );
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document.write( "Begin by making 300 minutes into a fraction by putting a 1 under it:\r\n" );
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document.write( "Now we have to decide which of these two unit fractions that we can make \r\n" );
document.write( "with \"60 minutes = 1 hour\" we will use to multiply   by.\r\n" );
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document.write( "We notice that  has \"minutes\" in the numerator.  We\r\n" );
document.write( "want to get rid of \"minutes\" and have only \"hours\", so we choose the unit\r\n" );
document.write( "multiplier (fraction) that has \"minutes\" in the denominator so that the\r\n" );
document.write( "\"minutes\" will cancel out.  So we use the unit multiplier fraction  \r\n" );
document.write( "because it has minutes in the denominator.  So we have:\r\n" );
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document.write( "Then we cancel the words \"minutes\"!  Yes, we can cancel words just like we \r\n" );
document.write( "can cancel numbers.  So we cancel the words \"minutes\":\r\n" );
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document.write( "Now the words \"minutes\" are gone and all we have are\r\n" );
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document.write( "which is\r\n" );
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document.write( "And since 300÷60 = 5, the answer is\r\n" );
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document.write( "5 hours.\r\n" );
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document.write( "Edwin
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