November 22, 2013
- 2. Notes: Complete Guides to a) Fractions b) Simplifying Posted @v6 math (pages) Tuesday: Test on Simplifying (prime factorization, GCF, and factoring)
- 3. Warm-Up: 2. 3 3/7 + (-2 3/8) 2 Simplify: 4. 10m – 15n 5 7. 15x2 + 21x6 5. 20a6b5 6. 45 10x – 10 35a2b3 2 = ?_ 3 18 36__ = 4 (x - 8) 9__ 2(x – 1) ?__ (x - 2)
- 4. Warm-Up:
- 5. Decimals: Objectives 1. 2. 3. 4. 5. 6. Read decimals Write decimals Compare the value of decimals +, -, x, / decimals Round decimals to nearest tenth Round decimals to nearest hundredth
- 6. Decimals: Definition A decimal is a fraction with a denominator that is a multiple of 10. The decimal (.) is used to indicate place value. Examples: 3 equals 0.3 stated as "three tenths" 10 18 equals 0.18 stated as "eighteen hundredths" 100 Each decimal expression with a value less than 1 is preceded by a leading zero to emphasize the presence of a decimal. For example, .7 is correctly written as 0.7
- 7. Decimals: Definition A decimal is a fraction with a denominator that is a multiple of 10.
- 9. Decimals: Reading Reading 1. 2. Read the decimal point as the word “and” Read the decimal fraction on the right Example: 8.3 = “eight and three tenths” 4.06 = “four and six hundredths” 0.5 = “five tenths The word „point‟ is not a number and is not used when reading decimals.
- 10. Decimals: Adding and Subtracting Place the numbers in the columns so the decimals are lined up. Add or subtract from left to right. Add or Subtract as indicated: 16.4 21.8 + 3.0 .7 .750 + .324 .7 00 - .050 Safety Point: Zeros may be added to help line up decimals – don’t include in final answer!
- 11. Decimals: Multiplying Place decimal correctly! Multiply numbers; in the product (answer), count decimal places right to left equal to the total decimal places in the numbers being multiplied. 1.2 x 3.2 24 36 384. = 3.84 Find the product: .7 x .050
- 12. Decimals: Multiplying (cont‟d) Add zeros where needed to ensure correct placement of decimal in answer Example: 0.11 x .33 Find the product: 0.11 x 0.33 33 33 0363. = 0.0363 .12 x .14
- 13. Multiplying by Decimal Movement Multiplying by 10, 100, 1,000 can be done by moving decimal to the right one space for each zero in the number by which multiplying Example: 1.6 x 10 = 1.6 = 16 5.2 x 100 = 5.20 = 520 .7 • 10 = .8 • 100 =
- 14. Decimals: Dividing a Decimal To divide by a whole number, place decimal in quotient directly above decimal in dividend 3.5 5 17.5 - 15 25 - 25 0 Find the quotients: 22.3 ÷ 8 35.7 ÷ 4
- 15. Decimals: Dividing by a Decimal Move the decimal in the divisor to the right until the number is a whole number. Then move the decimal in the dividend the same number of spaces. . 0.3 6.96 23.2 3 69.6 - 6 9 Find the quotient: 12.1 ÷ .8 - 9 6 -6 0
- 16. Reminders: *This week‟s class work due today *Alt. Khan due today, regular Khan Sunday
- 18. Fractions/Decimals & Percent Unit