1 / 35

Divisibility Rules

Divisibility Rules. A number is divisible by … 2 , if the ones digit is even ( 0, 2, 4, 6, 8 ) Example: 5 8 because there is an 8 in the ones place. A number is divisible by … 3 , if the sum of its digits is divisible by 3 Example: 81 because 8 + 1 = 9 and 9 is divisible by 3.

skip
Download Presentation

Divisibility Rules

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Divisibility Rules

  2. A number is divisible by … • 2, if the ones digit is even (0, 2, 4, 6, 8) • Example: 58 because there is an 8 in the ones place

  3. A number is divisible by … • 3, if the sum of its digits is divisible by 3 • Example: 81 because 8 + 1 = 9 and 9 is divisible by 3

  4. A number is divisible by … • 4, if the last 2 digits are divisible by 4 • Example: 832 because 32 is divisible by 4

  5. A number is divisible by … • 5, if the ones digit is a 0 or a 5 • Example: 1025 because there is a 5 in the ones place

  6. A number is divisible by … • 6, if the number is divisible by 2 AND 3 • Example: 48 • There is an 8 in the ones place so it is divisible by 2 • 8 + 4 = 12 and 12 is divisible by 3, so 48 is divisible by 3

  7. A number is divisible by … • 9, if the sum of the digits is divisible by 9 • Example: 468 because 4 + 6 + 8 = 18 and 18 is divisible by 9

  8. A number is divisible by … • 10, if the ones digit is a zero • Example: 2010 because the ones digit is a 0

  9. A number is divisible by … • 10, if the number ends in zero • Example: 50 because the number ends in zero

  10. Fractions

  11. To simplify fractions – you need to find the greatest common factor of the numbers • Use your divisibility rules to help you • Example:

  12. Equivalent Fractions: are fractions that have the same value OR simplify to the given fraction • Example: both fractions reduce to

  13. To simplify fractions – you need to find the greatest common factor of the numbers • Use your divisibility rules to help you • Example:

  14. Improper Fractions & Mixed Numbers

  15. Improper Fractions • An Improper Fraction is one where the numerator is larger than denominator

  16. Convert Improper Fractions to Mixed Numbers • To convert and improper fraction into a mixed number follow these 3 steps: • .Divide the numerator by the denominator • Turn your remainder into a fraction • Reduce your fraction to simplest form

  17. Examples • . • . • . • .

  18. Mixed Numbers • A mixed number is a special fraction that has a whole number and a fraction

  19. Convert Mixed Numbers to Improper Fractions • To convert and improper fraction into a mixed number follow the recycling method: • .Multiply the denominator by the whole number • .Add the numerator to the product found in previous step. • Place the sum found in Step 2 over the old denominator in your mixed number

  20. Use the “Recycling Method” to help us with this… • . • . • . • .

  21. We can also remember to not get M.A.D. when we have to convert mixed numbers to improper fractions….. Multiply Add Denominator (keep same one)

  22. Adding & Subtracting.Fractions

  23. Fractions need to have common denominators in order to add or subtract them. If they do skep to step #3 • To get common denominator: find lowest common denominator (LCD) • Create equivalent fractions with he least common denominator (LCD) • Add or subtract the numerators. Then add or subtract the whole numbers (if they are mixed numbers)

  24. For some subtraction problems you may need to borrow one whole in order to subtract. Do this and write the fraction as an improper fraction • .Write your fraction with the common denominator answer • .Reduceyour answer to simplest form (if your solution is an improper fraction, make it into a mixed number)

  25. Examples • . • . • . • . • . • . • .

  26. Multiplying & Dividing.Fractions

  27. If the fractions are mixed numbers, make them into improper fractions • To divide you must Keep, Switch, Flip. Keep the first fraction, Switchthe multiplication sign to division, Flip the other fraction to its reciprocal • You cross simplify to make it a simpler problem • Multiply the numerators and then multiply the denominators • .Reduce your answer to simplest form (if your solution is an improper fraction, make it into a mixed number)

  28. Examples • . • . • . • . • . • . • . • . • .

  29. Fractions Decimals

  30. Convert Decimals to Fractions • Write the decimal the way you say it. • Example: 0.25 “Twenty-five hundredths • Reduce the fraction to simplest form. • Example:

  31. Convert Fractions to Decimals • Divide the numerator by the denominator. • Use long division. • Check with your calculator. • Example:

  32. Examples • . • . • . • . • . • . • . • . • . • .

  33. Rational Numbers

  34. Rational Numbers • Rational Numbers terminate or repeat. • How do we know if a number is terminating or repeating number? Convert the number to a decimal. • Terminating numbers are numbers that end or stop. • Example: 0.75, 2, • Repeating numbers are numbers that have a repeating pattern. • Example:

  35. Examples Terminating Repeating • . • . • . • . • . • . • . • . Terminating Repeating Terminating Terminating Neither Neither

More Related