Warm Up Problem of the Day Lesson Presentation Lesson Quizzes

Warm Up Order the numbers from least to greatest. 1. 242, 156, 224, 165 2. 941, 148, 914, 814, 721 3. 345, 376, 354, 397 156, 165, 224, 242 148, 721, 814, 914, 941 345, 354, 376, 397

Problem of the Day Lupe is taller than Reba and shorter than Miguel. Tory is shorter than Lupe but taller than Reba. List the four brothers and sisters in order from tallest to shortest. Miguel, Lupe, Tory, Reba

Place value can help you understand and write and compare decimal numbers.

Additional Example 1: Reading and Writing Decimals Write each decimal in standard form, expanded form, and words. A. 1.07 B. 0.03 + 0.006 + 0.0009 Expanded form: 1 + 0.07 Word form: one and seven hundredths Standard form: 0.0369 Word form: three hundred sixty-nine ten-thousandths

Additional Example 1: Reading and Writing Decimals Write the decimal in standard form and expanded form. C. fourteen and eight hundredths Standard form: 14.08 Expanded form: 10 + 4 + 0.08

Check It Out: Example 1 Write each decimal in standard form, expanded form, and words. A. eleven and two hundredths B. 3.608 11.02 ;10 + 1 + 0.02 3 + 0.6 + 0.008; three and six hundred eight thousandths

Check It Out: Example 1 continued Write each decimal in standard form and expanded form. C. 20 + 1 + 0.2 + 0.01 21.21; twenty-one and twenty-one hundredths

Additional Example 2: Earth Science Application The star Wolf 359 has an apparent magnitude of 13.5. Suppose another star has an apparent magnitude of 13.05. Which star has the smaller magnitude? Line up the decimal points. Start from the left and compare the digits. 13.50 Look for the first place where the digits are different. 13.05 0 is less than 5. 13.05 < 13.50 The star that has an apparent magnitude of 13.05 has the smaller magnitude.

Check It Out: Example 2A Tina reported on a star for her science project that has a magnitude of 11.3. Maven reported on another star that has a magnitude of 11.03. Which star has the smaller magnitude? 11.30 11.03 0 tenths is less than 3 tenths, so 11.03 < 11.30. The star that has a magnitude of 11.03 has the smaller magnitude.

Check It Out: Example 2B Marci shipped two packages. One weighed 7.231 pounds and the other weighed 7.229 pounds. Which package weighed less? 7.231 7.229 2 hundredths is less than 3 hundredths, so 7.229 < 7.231. The package that weighed 7.229 pounds weighed less.

Order the decimals from least to greatest. Additional Example 3A: Comparing and Ordering Decimals Order the decimals from least to greatest. 16.67, 16.6, 16.07 Compare two of the numbers at a time. Write 16.6 as “16.60.” 16.67 16.60 16.60 < 16.67 16.67 16.07 Start at the left and compare the digits. 16.07 < 16.67 16.60 16.07 Look for the first place where the digits are different. 16.07 < 16.60

Additional Example 3A Continued Graph the numbers on a number line. 16.6 16.67 16.07 16 16.1 16.2 16.3 16.4 16.5 16.6 16.7 16.8 16.9 17 The numbers are ordered when you read the number line from left to right. The numbers in order from least to greatest are 16.07, 16.6, and 16.67.

Order the decimals from greatest to least. Additional Example 3B: Comparing and Ordering Decimals Order the decimals from greatest to least. 0.08, 0.04, 0.1 0.08 0.04 Compare two of the numbers at a time. Start at the left and compare the digits. Write 0.1 as “0.10.” 0.08 > 0.04 0.08 0.10 0.10 > 0.08

Additional Example 3B Continued Graph the numbers on a number line. 0.04 0.08 0.1 0 0.02 0.04 0.06 0.08 0.10 The numbers from least to greatest are 0.04, 0.08, and 0.1.

Order the decimals 12.42, 12.4, 12.02 from least to greatest. Check It Out: Example 3A Order the decimals 12.42, 12.4, 12.02 from least to greatest. 12.42, 12.4, 12.02 12.42 12.02 12.4 12 12.1 12.2 12.3 12.4 12.5

Order the decimals 1.7, 2.05, 1.75 from greatest to least. Check It Out: Example 3B Order the decimals 1.7, 2.05, 1.75 from greatest to least. 2.05, 1.75, 1.7 1.75 1.7 2.05 1.5 1.6 1.7 1.8 1.9 2.0 2.1

Lesson Quizzes Standard Lesson Quiz Lesson Quiz for Student Response Systems

Lesson Quiz: Part I Write each in standard form, expanded form and words. 1. 8.0342 2. 10 + 8 + 0.3 + 0.006 3. eight and twelve hundredths 8 + 0.03 + 0.004 + 0.0002; eight and three hundred forty-two ten thousandths 18.306; eighteen and three hundred six thousandths 8.12; 8 + 0.1 + 0.02

Lesson Quiz: Part II 4. It takes Pluto 246.7 years to orbit the Sun, and it takes Neptune 164.8 years. Which takes longer to orbit the Sun? 5. Order the decimals from least to greatest: 16.35, 16.3, 16.5. Pluto 16.3, 16.35, 16.5

Lesson Quiz for Student Response Systems 1. Which of the following represents 3.0727 in the expanded form and words? A. 3 + 0.07 + 0.002 + 0.0007; three and seven hundred twenty-seven thousandths B. 3 + 0.7 + 0.072 + 0.727; three and seven hundred twenty-seven thousandths C. 3 + 0.07 + 0.072 + 0.0727; three and seven hundred twenty-seven ten-thousandths D. 3 + 0.07 + 0.002 + 0.0007; three and seven hundred twenty-seven ten-thousandths

Lesson Quiz for Student Response Systems 2. Which of the following represents 25 + 0.9 + 0.007 in the standard form and words? A. 25.907; twenty-five and nine hundred seven thousandths B. 25.907; twenty-five and nine hundred seven hundredths C. 25.97; twenty-five and ninety seven hundredths D. 25.97; twenty-five and nine hundred seven thousandths

Lesson Quiz for Student Response Systems 3. Which of the following represents ‘twenty-three and six hundredths’ in the standard form and expanded form? A. 23.06; 20 + 3 + 0.006 B. 23.06; 20 + 3 + 0.06 C. 23.006; 20 + 3 + 0.06 D. 23.006; 20 + 3 + 0.006

Lesson Quiz for Student Response Systems 4. The atomic weight of Gallium is 69.723, Germanium is 72.64, Copper is 63.546 and Zinc is 65.409. Which element has the highest atomic weight? A. Gallium B. Germanium C. Copper D. Zinc

Lesson Quiz for Student Response Systems 5. Which of the following represents the given decimals ordered from least to greatest? 13.52, 13.3, 13.08 A. 13.08, 13.3, 13.52 B. 13.52, 13.08, 13.3 C. 13.3, 13.08, 13.52 D. 13.3, 13.52, 13.08