document.write( "Question 615814: A yogurt company blends regular yogurt that is 4% fat with its no-fat yogurt to obtain low-fat yogurt that is 1% fat. How many pounds of non-fat yogurt must be mixed to obtain 60 pounds of low-fat yogurt? \n" ); document.write( "
Algebra.Com's Answer #387321 by dragonwalker(73)![]() ![]() ![]() You can put this solution on YOUR website! (note * symbol used for multiplication sign so as not to confuse the algebra unit x)\r \n" ); document.write( "\n" ); document.write( "Firstly you want to look at what you know. \n" ); document.write( "1) There will be a final product of 60lbs of yogurt \n" ); document.write( "2) There are two types of yogurt, one that is 0% fat and the other 4% (which can also be written as 0.04 (4/100)\r \n" ); document.write( "\n" ); document.write( "The 4% fat has a greater amount of fat than the final product of 1% (+3) \n" ); document.write( "The 0% fat has a lesser amount of fat than the final product of 1% (-1)\r \n" ); document.write( "\n" ); document.write( "So for every unit of 4% we need to lower it by 3 to get the 1%. \n" ); document.write( "How can we lower it by 3? Well one unit of 0% fat would lower by one (-1), so 3 units of 0% would lower it by 3?\r \n" ); document.write( "\n" ); document.write( "So for 1 unit of 4% we need to add 3 units of 0% (a total of 4). \n" ); document.write( "So now we need to see how big one of these units is. \n" ); document.write( "We need a total of 4 units to mix the yogurt correctly so we need to see how many times 4 goes into 60 lbs. Let us say that x is the size of one unit so:\r \n" ); document.write( "\n" ); document.write( "4x = 60 \n" ); document.write( "x = 60/4 \n" ); document.write( "x = 15\r \n" ); document.write( "\n" ); document.write( "so each unit is 15 lbs\r \n" ); document.write( "\n" ); document.write( "So how many units of 4% did we need? 1 unit (or 1x).\r \n" ); document.write( "\n" ); document.write( "so: 1x = 1 * 15 \n" ); document.write( " = 15 lbs \n" ); document.write( "How much 0% did we need? 3 units.\r \n" ); document.write( "\n" ); document.write( "So 3 units (or 3x) = 3 * 15 \n" ); document.write( " = 45\r \n" ); document.write( "\n" ); document.write( "So we need 45 lbs of 0%\r \n" ); document.write( "\n" ); document.write( "So we need 15 lbs of 4% and 45 lbs of 0%\r \n" ); document.write( "\n" ); document.write( "To check:\r \n" ); document.write( "\n" ); document.write( "we know x = 15\r \n" ); document.write( "\n" ); document.write( "so if we decide to multiply the amounts with the concentrations then we should end up with a balanced equation.\r \n" ); document.write( "\n" ); document.write( "How much fat in 60 lbs of 1 %?\r \n" ); document.write( "\n" ); document.write( "1 % is one hundredth or 1/100 = 0.01 \n" ); document.write( "so the amount of fat is 60 * 0.01 = 0.6 lbs of fat\r \n" ); document.write( "\n" ); document.write( "4% is 4/100 = 0.04\r \n" ); document.write( "\n" ); document.write( "So 0.04 * 15 = 0.6 lbs of fat!!! \n" ); document.write( "The 0% yogurt doesn't add any fat, but just makes the weight up to 60 lbs.\r \n" ); document.write( "\n" ); document.write( "However although finding out how much fat you need in the final product and then working out how to get that amount of fat using the 4% would work for this, the other method is needed if both yogurts being mixed have some fat. \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |