MLS                                                                                       Yolanda Volcimus

Harvard                                                                              1/22/13

A percent is used to describe an amount of change in a number. There are numerous strategies that can be used to determine the percent of a number. In some cases, we can even find some real-world applications where percent is used. In addition, these real-world applications are necessary to have an understanding of the "story" behind the situation in order to apply the specific strategies. Therefore, there a various strategies that are involved in percentage.

       Percent of Change is the amount stated as percent; it is one of the strategies to determine the percent of a number. The two types of percent of change are percent increase and percent decrease. Percent increase is when the amount of a number improved; however, percent decrease is when the amount diminishes. The percent of change of a number is calculated as percent of change= amount of change over original amount. For example, in the statement "50 is decreased to 40", you would solve it by doing 50-40/50 based on the formula. Then, it would be 10/50 which is equal to 20%. Therefore, "50 is decreased to 40" is a 20% decreased. In addition, "25 is increased to 40" is a 37.5% increased because I set the problem as 40-25/40= 15/40= 0.375= 37.5%. That is to say, a strategy to find the percent of a number is percent of change.
       Furthermore, people can use discount which is a real-world application to find the percent of a number. Discount is a deduction from the original cost of an item. To find the discount of a number, we use the formula discount/original. It is necessary to have an understanding of the "story" behind the situation in order to apply the specific strategies because if we apply the wrong formula, we will end up with the incorrect percentage. For instant, if we have the story "At a store, an IPod was $50; however, it was on sale for 10% off. What was the new price?" If we have this problem, we know the strategy we would use is discount because 10% is being deducted from $50 and the new price would be $45.            

    Another strategy we can use to determine the percent of a number is commission. Commission is a free paid to a person who makes a sale. Commission is calculated by commission rate x sale = commission. In a real-world application, "A car is sale for $50,000 and Marvin gets 5% of this money? What is the commission?" Based on our understanding of the story, we know the correct strategy is commission because it is a free paid for Marvin. Marvin would receive $2,500 from the original amount.
     The last strategy we can use to find the percent of a number is revenue. Revenue is the amount of money brought in from a sale. After the costs are subtracted from the revenue, the amount remaining is the profit. For example, "the profit of 10 shirts was $50 which is 80% of the revenue. What is the revenue?" The revenue is $62.50 because I set a proportion of 80/100 = 50/x = 80x = 5,000= 5,000/80= 62.5.
        To wrap it all up, percent is an amount of change. The four strategies that are used to find the percent of a number are percent of change, discount, commission, and revenue. These strategies are all used in real-world application and the story is crucial in order to determine which strategy to use. In conclusion, the percentage of a number can be measures in many ways.