FRACTION REVIEW 2 Adding Subtracting Multiplying and Dividing

FRACTION REVIEW #2 Adding, Subtracting, Multiplying and Dividing Fractions and Mixed Numbers

ADDING AND SUBTRACTING FRACTIONS

1. YOU MUST HAVE COMMON DENOMINATORS! 1+ 1 2 3

2. FIND COMMON DENOMINATORS Both 2 and 3 go into 6. 3 2 6 new denominator. 6 This will be my 3 + 2 6 6

3. ADD THE NUMERATORS (DENOMINATOR STAYS THE SAME) 3 + 2 = 5 6 6 6

4. CAN WE REDUCE?

5. WE FOLLOW THE SAME STEPS TO SUBTRACT. 1. You MUST have common denominators. 2. Find common denominators. 3. Now that we have common denominators, we subtract the numerators. 4. Can we reduce? 3 6 2 = 6

PRACTICE 3 /4 + 1/3 = 1 /4 + 1/3 = 2/3 + 1 /2 =

ADDING AND SUBTRACTING MIXED NUMBERS

ADDING AND SUBTRACTING MIXED NUMBERS 1. Make into an improper fraction, add, then change back into a mixed number. (This might take a few more steps, but is better in the long run!)

1. CHANGE INTO AN IMPROPER FRACTION 3 19 + = 2 8

2. ADD/SUBTRACT THE FRACTIONS Don’t forget, you MUST have a common denominator to add or subtract fractions! 3 12 + 19 = 31 8 8 2 8 What number to both 2 and 8 go into? Then add the numerators, keep the denominators the same.

3. CHANGE BACK TO A MIXED NUMBER 31 8 3 7 8

PRACTICE: 3 2 /3 + 9 6 /7 1. make into improper fractions 2. find common denominators 3. add numerators 4. 284 convert back to mixed numbers 21 11 3 + 69 7 11 21 21/ 284 13

PRACTICE: 12 6 /13 - 7 1 /2 = 8 2 /9 + 12 2 /3 = 9 4 /9 - 3 3 /18 =

MULTIPLYING FRACTIONS

1. MULTIPLY THE NUMERATORS 1 x 2 = 2 3

2. MULTIPLY THE DENOMINATORS 1 2 = x 2 3

3. SIMPLIFY I can divide a 2 out of both 2 and 6 2 divided by 2 is 6 divided by 2 is 1 3

WHOLE NUMBER AND FRACTION MULTIPLICATION Make the whole number into a fraction by putting it over 1. 2 x 3 1 4

MULTIPLY THE NUMERATORS 2 1 x 3 =2 x 3 6 = 4

MULTIPLY THE DENOMINATORS

DIVIDE AND SIMPLIFY 6 4 1 2 =1 4 2 4 / 6

PRACTICE 3 5 x 1 2 1 x 2 4 2 5

MULTIPLYING AND DIVIDING MIXED NUMBERS

1. CONVERT TO AN IMPROPER FRACTION. Get MAD! (multiple the denominator and the whole number, add that to the numerator, denominator stays the same). 6 ²⁄₇ x 3 ³/₄ ⁴⁴⁄₇ x ¹⁵/₄

2. CAN YOU CROSS SIMPLIFY? ⁴⁴⁄₇ x ¹⁵⁄₄ Yes, I can take 4 out of both 44 and 4. ¹¹⁄₇ x ¹⁵/₁

3. MULTIPLY THE NUMERATORS ¹¹/₇ 11 x 15 = 165 x ¹⁵/₁

4. MULTIPLY THE DENOMINATORS ¹¹/₇ 7 x 1=7 ¹⁶⁵⁄₇ x ¹⁵/₁

5. CHANGE BACK INTO A MIXED NUMBER. ¹⁶⁵⁄ ₇ 7 / 165

6. CAN YOU REDUCE? 23 ⁴/₇ No!

DIVIDING MIXED NUMBERS To divide a mixed number, follow steps 1, 2, 3 then multiply by the reciprocal. 6 ²⁄₇ ÷ 3 ³/₄

- Slides: 33