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Lesson 55. Common Denominators. Notes. Mental Math. Links. Activity. Proficiency. Homework. Fact Test. Mental Math. Count by 7’s from 7 to 84 8 x 325 329 + 50 275 - 99 $12.50 +- $5 Double 3 ½ 600/20 8 x 5, + 2, ÷ 6, x 7, + 7, ÷ 3, x 4, ÷ 7.
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Lesson 55 Common Denominators
Notes Mental Math Links Activity Proficiency Homework Fact Test
Mental Math • Count by 7’s from 7 to 84 • 8 x 325 329 + 50 • 275 - 99 $12.50 +- $5 • Double 3 ½ 600/20 • 8 x 5, + 2, ÷ 6, x 7, + 7, ÷ 3, x 4, ÷ 7
Common Denominator- When the denominators of two or more fractions are equal. • To find the common denominator of two fractions, we find a common multiple of the denominators. The least common multiple of the denominators is called the least common denominator of the fractions. • ½ ?/4 ½ = 2/4 2/4 + ¼ ?/4 ¼= ¼ +1/4 ¾ Divide the denominator into 4 then multiply by the numerator.
Example #1 1/2- 1/6 = 1/2 = 3/6 - 1/6 = - 1/6 2/6 = 1/3 Example #2 3/8 + ¼ = 3/8 3/8 + 1/4+2/8 5/8
Adding and subtracting Fractions http://www.math.com/school/subject1/practice/S1U4L3/S1U4L3Pract.html Adding and subtracting Fractions http://www.aaamath.com/B/g66k_ax1.htm
Activity Half of a gallon is a half gallon. Half of a half is a quart. Half of a quart is a pint. Half of a pint is a cup. How many cups of water equals a gallon of water?
Lesson 55 Practice A-F Complete #’s 1-10