Watch Video on Discount Formula – Pre Algebra Help
Friday, March 26th, 2010
Access full lesson containing this video at: http://www.yourteacher.com/prealgebra/discountformula.php Students solve word problems using the “discount” formula, which states: original price x rate of discount = discount. Students also solve word problems using the “sale price” formula, which states: original price — discount = sale price. For example: A tennis racket marked at $110.50 is on sale at 20% off. What is the discount? What is the sale price? Students also solve word problems using the “rate of discount” formula, which is the same as the percent decrease formula: amount of change/ original number. For example: An old video game is marked down from $48 to $18. What is the rate of discount?
Duration : 0:3:8
Access full lesson containing this video at: http://www.yourteacher.com/algebra1/percentproblems.php Students learn to solve “percent” word problems, such as the following. What is 24% of 175? Note that “what” means “x”, “24%” means “24/100″, “is” means “equals”, “of” means “times”, and “175″ means “175″. So this word problem can be translated into the equation x = 24/100 times 175.
Access full lesson containing this video at: http://www.yourteacher.com/algebra1/coinproblems.php Students learn to solve “value” word problems, such as the following. Martin has a total of 19 nickels and dimes worth $1.65. How many of each type of coin does he have? Note that this problem requires a chart to organize the information. The chart is based on the total value formula, which states that the number of coins times the value of each coin = the total value. The chart is then used to set up the equation.
Access full lesson containing this video at: http://www.yourteacher.com/algebra1/algebrawordproblems.php Students learn to solve “number” word problems, such as the following. One number is four times as large as another. The sum of the numbers is 45. Find the numbers. Since the first sentence states that one number is 4 times as large as another, the numbers can be represented as x and 4x. Since the second sentence states that the sum of the numbers is 45, the equation can be set up as x + 4x = 45.
Access full lesson containing this video at: http://www.yourteacher.com/algebra1/simplifyingradicals.php Students learn to simplify a square root by setting up a factor tree for the number inside the radical. If a factor pairs up in the factor tree, then it comes out of the radical. If a factor does not pair up, then it stays inside. Students also learn to simplify a cube root by setting up a factor tree for the number inside the radical. If a factor is part of a group of three factors that are the same, then it comes out of the radical. If a factor is not part of a group of three factors that are the same, then it stays inside.