November 21, 2013

Today:

Test Make-Up: Today @ LunchWarm-Up

One-Inch RulerOperations with Fractions

Warm-Up:

1. Solve for 'a' S = 2(a + b) + 2ab

2.

3.

4.

Vocabulary: Fractions: From the Latin fractiō:  a breaking into pieces, also from the Latin fractus:  broken

English Words from the Latin Root Fractus: fracture, infraction, fragile, frail

Fractions are a SINGLE NUMBER and can be placed on the number line. All positive proper fractions are a number between 0 and 1.

A fraction is defined as a “part – whole” relationship of a number. 3 out of 5 students were girls. The fraction is 3/5

Vocabulary: The denominator "5" represents the whole, and the numerator "3" represents the part. The original quantity 5 has been "broken" into 2 parts.Since Fractions are used to show the relationship between the part and the whole, we don't always know what the actual quantity is.

Example: 4 out of 5 students want school to start later. Does this mean only 5 students were asked? It could. But what if 100 students were surveyed? Then how many said they preferred to start later.

Because fractions are simplified, we don't always know what the original quantity is, which isn't the purpose of a fraction anyway.

Formulas & Vocabulary: Adding & Subtracting Fractions with the same Denominator:o Simply add the numerators, the denominator stays the same

o Examples: 1/8 + 4/8 = 5/9 - 1/9 = Adding Fractions with different Denominators: The formula for adding is: a/b + c/d = ad + cb / bdo Example: 1/5 + 3/8 = 1(8) + 5(3) / 5(8) = 8 + 15 / 40 = 23/40

Subtracting Fractions with different Denominators:

The formula for subtracting is: a/b - c/d = ad - cb / bdo Example: 4/5 - 3/8 = 8(4) - 5(3) / 5(8) = 32 -

15 / 40 = 17/40

Class Work: Ruler

A. Label each line of the top ruler with the proper fraction:

B. Answer (simplify) and place the mark on the bottom ruler 1. 4/32 2. 7/4 - 7/8 3. 4/644. 3/4 ÷ 45. 6/8 • 1/4 6. 3/16 + 2/8 7. 14/32 + 16/32

Class Work: Fraction Worksheet