Percentages for Beginners

Advance to level 2 by learning how to work with percentages, calculate percentage change, apply shortcuts to handle increases or decreases, and express one value as a percentage of another.

Master the 25 percent shortcut: divide by four, halving twice for mental calculation, and apply to values like 80 or 300 to adjust numbers by a percent.

Learn how to decrease a number by a percent using mental shortcuts and cross-multiplied methods, such as 20 percent off 70, yielding 56, and 50 percent of 30 equals 15.

Delve into level 3 real life applications of percentages, including discounts, taxes, profit and loss, and both simple and compound interest, with practice questions and a pre-video quiz.

Learn to apply a 30 percent discount by calculating sale price and savings from an original price, using 800 dollars to get 560 dollars sale price and 240 dollars saved.

Apply percentages to discounts by calculating the price after discount 1400 and the price before discount 1750 from a 20 percent sale saving 350 rupees.

Explore how to compute discount-based prices using percentage reductions and successive discounts, with examples on an air conditioner and textbooks calculating mark price, sale price, and bulk costs.

Learn how to convert between before-tax and after-tax amounts using percentages, with a 15% tax example: calculate pre-tax price and tax amount from inclusive totals.

Determine tax payable using tax brackets for a chargeable income of 42,000. Apply zero tax on the first 20k, 2% on the next 10k, and 7% on the remainder.

Calculate Mr. Lee's taxable income by subtracting total reliefs from 84,000, then apply the tax brackets to determine the tax payable and the take-home pay of about 82,801.80.

Learn how to apply percentage to profit and loss, using cost price and selling price with a newspaper example, and calculate profit or loss as a percentage.

Practice-based lesson on profit and loss: calculate cost versus selling price, express loss as a percentage of selling price, include tax effects, and determine required selling prices to preserve profits.

Understand simple interest by applying the principal amount to a rate of interest per annum, illustrated with an 8 percent example over three years to show earned interest and total.

Practice simple interest using the SI = PRT/100 formula through questions: 48000 at 6% for 2 years, 16800 to 18900 at 5%, and 4800 over 7 months with 119 interest.

Explore compound interest by applying the rate to the growing balance, contrast it with simple interest, and illustrate the formula with a 10 percent, 2000 principal example.

Practice compound interest calculations using principal, rate, and time, including yearly and monthly compounding, to find total amounts and interest.

learn to calculate percentage error by comparing measured and actual values, using the formula percentage error equals (error over actual) times 100, with examples like a 5,000 vs 4,000 bill.

Explain how commission adds to a fixed salary by paying a percentage of sales, illustrated with a $40,000 base and 2 percent on $250,000.