Common Denominators Improper Fractions and Mixed Numbers In

Common Denominators Improper Fractions and Mixed Numbers

� In order to add or subtract fractions, you MUST have common denominators! � ⁴⁄₉ + ¹⁄₃ � Write out the factors 1 -10 for 9 and 3 � 9, 18, 27, 36, 45, 54, 63, 72, 81, 90 � 3, 6, 9, 12, 15, 18, 21, 24, 27, 30

� 9, 18, 27, 36, 45, 54, 63, 72, 81, 90 � 3, 6, 9, 12, 15, 18, 21, 24, 27, 30 � Now choose a number that appears on both lines of numbers…. this is your new denominator!

� ⁴⁄₉ + ¹⁄₃ � If you choose 9 for your “common number, ” what did you multiply to get it? � ⁴⁄₉ (this fraction already has 9 as the denominator) � ¹⁄₃ = ⁄₉ (I multiplied 3 times 3 to get the denominator of 9)

� ⁴⁄₉ (this fraction already has 9 as the denominator) This fraction will stay the same. � ¹⁄₃ = ⁄₉ (I multiplied 3 times 3 to get the denominator of 9) �In order to get the new numerator, I have to multiply the original numerator by 3 also. Remember, when you multiply a number times 1, you get that same number. For a fraction if the numerator and the denominator are the same it is equal to 1, so the fraction is the same amount written in a different fraction form.

� 7 ³⁄₅ When there is a whole number and a fraction together, it is called a mixed number. � ¹²⁄₅ When the numerator is larger than the denominator, it is called an improper fraction.

� M-multiply � A-add � D-denominator stays the same

� Multiply the denominator by the whole number: � 8 x 9 = 72

� Add your answer to the multiply step to the numerator � 8 x 9 = 72 � 72 + 7 = 79 (new numerator)

� New numerator after “getting MAD” � Keep the denominator the same:

� Remember � 8 the fraction bar means divide! / 79 � We divide the denominator into the numerator. He remainder is the new numerator and the denominator stays the same.