Rounding Numbers and Place Value

Rounding Numbers

• Numbers rounded to the nearest whole number:
  • 31.3 rounds to 31
  • 5.8 rounds to 6
  • 16.5 rounds to 17
  • 3.8 rounds to 4
• Rounding to the nearest hundredth:
  • 7.36 remains 7.36
• Rounding to the nearest whole number gives 5 from 5.0

Writing Time in Seconds

• Time representation in seconds:
  • Eighteen and nine hundred twenty-three thousandths seconds corresponds to 18.923 seconds

Ordering Decimals

• Decimals ordered from least to greatest:
  • 38.001, 38.01, 38.1
  • 3.052, 3.25, 3.52

Determining Place Value of Digits

• Place values of underlined digits in given numbers:
  • In 3.178, the tenths place is 1
  • In 5.931, the tens place is 5
  • In 4.206, the hundredths place is 0
  • In 2.374, the thousandths place is 4

Comparing Numbers

• Number comparisons demonstrating greater values:
  • 2.85 is greater than 2.58
  • 6.8 is greater than 6.795
  • 3.08 is greater than 3.078
  • 0.021 is greater than 0.012
  • 11.010 is greater than 11.01
  • 14.82 is greater than 14.28

Rounding Numbers

• Rounding involves adjusting a number to a specified place value, affecting the digit in that place and possibly the digits to its right.
• To the nearest tenth:
  • 31.274 becomes 31.3
  • 5.793 becomes 5.8
  • 16.48 rounds to 16.5
  • 3.844 rounds to 3.8
• To the nearest hundredth:
  • 7.358 rounds to 7.36
• To the nearest whole number:
  • 4.875 rounds to 5

Writing Time in Words

• Time can be expressed in words for clarity:
  • Eighteen and nine hundred twenty-three thousandths seconds.

Ordering Decimals

• When ordering decimals from least to greatest, consider the value of each digit:
  • For the numbers 38.001, 38.01, and 38.1, the order is 38.001, 38.01, 38.1.
  • For 3.052, 3.25, and 3.52, the order is 3.052, 3.25, 3.52.

Value of Underlined Digits

• Identifying the value of a specific digit within a decimal is crucial:
  • In 3.178, the underlined digit is 7, representing 7/10.
  • In 5.931, the underlined digit 3 represents 3/100.
  • In 4.206, 2 represents 2/100.
  • In 2.374, 7 stands for 7/1000.
  • In 2.85, the underlined 8 is 8/10.
  • In 6.8, 8 is also 8/10.
  • In 3.08, the 8 represents 8/100.
  • In 0.012, 1 is 1/100.
  • In 11.01, 1 denotes 1/100.
  • In 14.28, 2 corresponds to 2/10.