Decimals

• What is the purpose of a decimal point?


  To separate a whole number from the fractional part
• Can decimals be positive or negative?


  Yes, decimals can be positive or negative
• How can a whole number be expressed?

  As a decimal, percentage, or fraction
• What is place value in a number?


  • The value of each digit in a number
  • Example: In 2.78, 2 is in the units place, 7 is in the tenths place, and 8 is in the hundredths place
• What is the place value of 2 in the number 2.782?


  2 is in the units place
• What is the place value of 7 in the number 34.397?


  7 is in the thousandths place
• How do you compare decimals?


  1. Compare digits in the same column
  2. Identify which is smallest or largest
  3. Example: 2.50 is greater than 2.15
• How do you add and subtract decimals?


  Align the decimal points and add or subtract as with whole numbers
• What is the result of adding 3.6 and 14.73?


  18.33
• What should you do when multiplying decimals?

  Add the decimal point in the answer based on the total number of decimal places
• What is the product of 3.72 and 2.3?


  1. 556
• How do you divide decimals?


  Keep the decimal point aligned and divide as with whole numbers
• What is the result of dividing 4.14 by 3?


  1. 38
• How do you divide a number by a decimal?


  1. Change to a fraction
  2. Multiply numerator and denominator by 10
  3. Divide the numbers
• What is the result of dividing 9 by 0.3?


  30
• What is the first step in dividing 9 by 0.3?


  Convert it to a fraction
• What is the fraction representation of 9 divided by 0.3?


  9/0.3 = 90/3
• What is the result of 90 divided by 3?


  30
• What is a decimal?


  A decimal is a fraction expressed in a special form
• Why is it important to align decimal points when adding or subtracting?


  To ensure accurate calculations
• What do you do if there are empty spaces when comparing decimals?


  Add zeros to fill in the spaces
• How do you determine the number of decimal places to add when multiplying?


  Add the number of decimal places from the factors
• Why must you keep decimal points aligned when dividing?


  To maintain the accuracy of the division