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We are learning to find percentages of 3 digit numbers. What does % mean? per for every cent 100 To find 1% of a number ÷ by 100 Find 1% of 225 225 ÷ 100 (move all digits 2 places to the right) 225. 2 .25 1% of 225 = To find 10% of a number ÷ by 10 Find 10% of 376 376 ÷ 10 (move all digits 1 place to the right) 376. 37.6 10% of 376 = Can we use this information To find 11% of a number? 10% + 1% = 11% Find 11% of 352 352 ÷ 100 = 3.52 352. 3.52 352 ÷ 10 = 35.2 352. 3 5.2 3.52 + 35.2 38 .72 Find 2% of 453 1% of 453 1% x 2 = 2% 453 ÷ 100 =4.53 The decimal point goes between the 9 and the 0. There are 2 digits after the decimal point in the sum so we need 2 digits after the decimal point in the answer 4.53 x 2 1 9.0 6 2% of 453 = 2x3=6 2 x 5 = 10 (carry the 1) 2x4=8+1=9 Use these methods to find 12% of 563 Hint: add together 10%, 1% and 1% 56.3 + 5.63 + 5.63 = 16% of 285 Hint: add together 10%, 6 x 1% 28.5 + (6 x 2.85) = Can you find 20% of 621? Hint: 20% = 10% + 10% or 10% x 2 621 ÷ 10 = 62.1 62.1 + 62.1 124.2 62.1 x 2 124.2 20% of 621 = 124.2