Percentage Increase and Decrease Lesson PDF

LC 2.1. Solve problems involving: percentage increase, and percentage decrease. LC 2.2. Solve money problems involving percentages: discount commission What is Percentage? When do we use Percentage? When dealing with percentage, it’s important...

LC 2.1. Solve problems involving: percentage increase, and percentage decrease. LC 2.2. Solve money problems involving percentages: discount commission What is Percentage? When do we use Percentage? When dealing with percentage, it’s important to analyze and categorize the given values. It is the ratio of amount to the base. It is always written as a percent. This is the ‘whole’ in the problem. The amount from where you take a percent of. The result after you applied the percent (rate) from a given number Determine the from the given problems. PRACTICE BASE RATE The total bill for your family dinner is 8,500 pesos. The restaurant charges 3% as service fee. You paid an additional 255 pesos. PERCENTAGE Determine the from the given problems. B3, G7 and B10 must answer RATE The luggage bags are on 30% sale. You bought one and paid 2,850 pesos less from the original price of 9500 pesos. PERCENTAGE BASE Determine the from the given problems. G14, B8 and G2 must answer PERCENTAGE After one year of keeping your money in the bank, you earned an additional 2000 pesos. This is because the bank offers 4% interest and your RATE saving is 50,000 pesos. BASE  P = (B)(R) If percentage is missing, P multiply the base and rate B = (P)/(R) If base is missing, B R divide the percentage by the rate R = (P)/(B) If rate is missing, divide the percentage by the base  What is 20% of 80? Rate: 20% P = (B)(R) Change the rate to decimal form Base: 80 Move the decimal point two P = (80)(.20) units to the left Perc: ? P = 16 The 20% of 80 is 16.  What is 75% of 132? Rate: 75% P = (B)(R) Base: 132 P = (132)(.75) Perc: ? P = 99 The 75% of 132 is 99. 10% is 0.10 but you can also use 0.1 instead. 20% is 0.2 30% is 0.3 Removing the extra 0 on the right will. make multiplication easier and faster... Just don’t forget to add another zero when converting it again to percent form. 90% is 0.9  Anna has a weekly allowance of 900 pesos. She allotted 540 pesos for her food. What percent of her allowance is for food? Rate: ? R = (P)/(B) Base: 900 R = (540)/(900) Perc: 540 R = 0.6 R = 60 % She allotted 60% of her allowance for food  At 100 % the device can work up to 620 minutes. If the device will shut down in 279 minutes, what is its current battery percent? Rate: ? R = (P)/(B) Base: 620 R = (279)/(620) Perc: 279 R = 0.45 R = 45 % The battery of the device is currently at 45 % The ticket price for a local movie is discounted by 15% for student viewers. If the original price is 180 pesos, how much will be deducted from it? 27 pesos less 21 is what percent of 84? 25 %  Jump Jump Some toyour to yourright left applications of ifPercentage ifyou youthink that thinkwill the thegiven thatchangegivenword wordof the value implies implies the base, Stand percentage eitherpercentage up. increase. decrease. increasing or decreasing it. Salary raise Discount Tax Sale Interest Deduction Salary Deduction Discount Interest Sale Taxraise  In case that clue words are missing, you can also follow this rule: If the new value is larger than the original value, then the percentage increases. If the new value is less than the original value, then the percentage decreases. Determine whether the given is percentage increase or decrease. An uncut version of a film lasts for 150 minutes. The released version is shorter by 15% time. How long does the released version last? Teacher Gwen will receive her holiday bonus which is equal to 30% of her monthly salary of 36, 000 pesos. If she will withdraw it together with her salary this month, how much should she expect to obtain? Jade bought a laptop that was on 12% sale. How much should she pay if the original price is 28,000 pesos? Determine whether the given is percentage increase or decrease. The updated minimum wage after the implementation of the law is 650 pesos from the previous rule of 605 pesos. To cover the additional expenses brought by the inflation, the restaurant changes the price of their main dish from 550 pesos to 640 pesos. Lucas used a voucher and bought the LEGO set for 440 pesos instead of the original price of 640 pesos. Difference of two values Percentage = Increase/Decrease Original value  The updated minimum wage after the implementation of the law is 650 pesos from the previous rule of 605 pesos. What rate of percentage increase does the implemented law entails? Percentage 45 Increase = = 0.07 = 7 % 605  To cover the additional expenses brought by the inflation, the restaurant changes the price of their main dish from 550 pesos to 640 pesos. What is the percentage increase represented by their prices? Percentage 640 – 550 90 Increase = = = 0.16 = 16 % 550 550  Lucas used a voucher and bought the LEGO set for 440 pesos instead of the original price of 640 pesos. What is the percentage decrease provided by the voucher? Percentage 640 – 440 200 Decrease = = = 0.31 = 31 % 640 640 Math Book, page 83 numbers 7 and 8 = 17 % = 14 %