Learn Fractions XII

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Fraction XIISubtracting Unlike Denominators: 

Fraction XII Subtracting Unlike Denominators By Monica Yuskaitis

Common Multiple: 

Common Multiple A number that is a multiple of two or more numbers. Some multiples of 4 andamp; 6 12, 24, 36

Least Common Multiple: 

Least Common Multiple The smallest common multiple of a set of two or more numbers. 6 = 6, 12, 18, 24, 30, 36 8 = 8, 16, 24, 32, 40, 48

Shortcut for Finding the Least Common Denominator or Least Common Multiple: 

Shortcut for Finding the Least Common Denominator or Least Common Multiple 1 3 1 9 - Check to see if the smaller denominator divides evenly into the larger denominator. If it does, use the larger denominator for your LCD or LCM. 3 will divide evenly into 9, so 9 is your LCD or LCM.

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Find the multiples of each denominator. 1 = 5, 10, 15, 20, 25, 30 1 = 10, 20, 30, 40, 50 - 5 10

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Compare the lists of multiples. Circle the common multiples between the two lists. 1 5 = 5, 10, 15, 20, 25, 30 1 10 = 10, 20, 30, 40, 50 -

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Use the lowest common multiple as the denominator. 1 5 = 5, 10, 15 ,20 ,25 ,30 1 10 = 10, 20, 30, 40, 50 -

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators This number is also called the least common denominator. 1 5 = 5, 10, 15 ,20 ,25 ,30 1 10 = 10, 20, 30, 40, 50 -

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Rewrite the fractions using the least common denominator or least common multiple. 1 5 1 10 - 10 10

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Find the equivalent fractions for 1/5 andamp; 1/10 with 10 as the denominator. 1 5 1 10 - 10 10 You know that 1/10 is equal to 1/10 so Put a 1 over the Bottom 10. 1

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Find the equivalent fractions for 1/5 andamp; 1/10 with 10 as the denominator. 1 5 1 10 - 10 10 To find the top number, ask yourself what do you multiply the 5 by to get 10. 1

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Find the equivalent fractions for 1/5 andamp; 1/10 with 10 as the denominator. 1 5 1 10 - 10 10 That’s right 2. Since you are looking for the equivalent fraction you know the top number must also be multiplied by 2. 1 x 2 = x 2 =

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Find the equivalent fractions for 1/5 andamp; 1/10 with 10 as the denominator. 1 5 1 10 - 10 10 To find the top number just multiply 2 x 1 to get your equivalent fraction. 1 x 2 = x 2 = 2

To Subtract Fractions With Unlike Denominators: 

To Subtract Fractions With Unlike Denominators Now just add the numerators. 1 5 1 10 - 10 10 Remember when subtracting fractions you never subtract the denominators. 1 x 2 = x 2 = 2 10 1

Subtract these Fractions: 

Subtract these Fractions 1 2 1 8 - Use the short cut to find the Least Common Denominator (LCD). 8 8

Subtract these Fractions: 

Subtract these Fractions 1 2 1 8 - Now find the equivalent fractions for 1/2 andamp; 1/8. 8 8 x 1 = x 4 = Ask what do you multiply 2 by to get 8 and what do you multiply 8 by to get 8.

Subtract these Fractions: 

Subtract these Fractions 1 2 1 8 - Since you are writing equivalent fractions, now multiply the top numbers by the same number you did in the bottom. 8 8 x 1 = x 4 = x 1 = x 4 =

Subtract these Fractions: 

Subtract these Fractions 1 2 1 8 - Now multiply across. 8 8 x 1 = x 4 = x 1 = x 4 = 1 4

Subtract these Fractions: 

Subtract these Fractions 1 2 1 8 - Subtract your new numerators. 8 8 x 1 = x 4 = x 1 = x 4 = 1 4 3 8

Subtract these Fractions: 

Subtract these Fractions 2 5 1 3 - Find the common Multiples for 5 and 3. Write This number As your new denominator. 15 15

Subtract these Fractions: 

Subtract these Fractions 2 5 1 3 - Ask yourself what you multiply the bottom number by to get 15. 15 15 x 5 = x 3 =

Subtract these Fractions: 

Subtract these Fractions 2 5 1 3 - Multiply the top number by the same number you did in the bottom. 15 15 x 5 = x 3 = x 5 = x 3 =

Subtract these Fractions: 

Subtract these Fractions 2 5 1 3 - Multiply across. 15 15 x 5 = x 3 = x 5 = x 3 = 5 6

Subtract these Fractions: 

Subtract these Fractions 2 5 1 3 - Now subtract your new numerators. 15 15 x 5 = x 3 = x 5 = x 3 = 5 6 1 15

Subtract these Fractions: 

Subtract these Fractions 5 6 1 8 - 24 24 x 3 = x 4 = x 3 = x 4 = 3 20 17 24

Subtract these Fractions: 

Subtract these Fractions 2 3 1 9 - 9 9 x 1 = x 3 = x 1 = x 3 = 1 6 5 9

Subtract these Fractions: 

Subtract these Fractions 4 5 2 3 - 15 15 x 5 = x 3 = x 5 = x 3 = 10 12 2 15

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