Math Chapter 4
2 1/3 - 1 2/3 (notes from 10/26)
2/3
6 1/4 - 2 3/4 (p. 305)
3 1/2
Order the set( 3.44, pie, 3.14, 3.4444444) (p. 273)
3.14, then pie, then 3.44, and 3.44444
1/2 + 1/4
3/4
Sophia ate 3/5 of a cheese pizza. Jack ate 1/5 of the cheese pizza and 2/5 of a pepperoni pizza. How much pizza did Sophia and Jack eat together.
3/5 + (1/5 + 2/5) = 3/5 + (2/5 + 1/5) = (3/5 +2/5) + 1/5 = 1 + 1/5 or 1 1/5 So Sofia and Jack ate 1 and 1/5 pizzas together
7 5/6 - 3 1/6 (notes from 10/26)
4 2/3
7/8 divided by 3/4 (p. 328)
4/3
15 cm is approximately how many inches?
5.91 in
1/2- (-2/5)
5/10 - 4/10 = 9/10
8 5/6 - 2 1/3 (p. 300)
6 1/2 estimates to 7
The side pieces of a butterfly house are 8 1/4 inces long. How many side pieces can be cut from a board measuring 49 1/2 inches long? (p. 330)
6/1 = 6
-4/9 - 2/15
6/17
5/9 + 2/9
7/9
10 4/5 - 2 1/5 (notes from 10/26)
8 3/5
Bar notation
A bar is drawn only over the digits that repeat
Common denominator
A common multiple of the denominators of two or more fractions
Find the fraction of the fish in the aquarium that are goldfish. Write in simplest form. Angelfish 0.4 Goldfish 0.15 Guppy 0.25 Molly 0.2
0.15 = 15/100 3/20 So 3/20 of the fish are goldfish
Compare -1/5/6 and -1 1/6
1 5/6 is less than -1 1/6
Convert 4.25 kilograms to pounds. Round to the nearest hundredth if necessary. (p. 321)
1 lb = 0.4536 km So 4.25 kg = 9.37 lbs (approx.)
Convert 5 km to miles
1 mile is approx. 1.61 km so 5km is approx. 3.11 mi.
Find 2/3 divided by 3 1/3. Write in simplest form (p. 329)
1/5
1/2 X 1/3 (p. 312)
1/6
3 divided by 1/4 (p. 328)
12 Dividng 3 by 1/4 is the same as multiplying 3 by the reciprocal of 1/4 which is 4.
Humans sleep about 1/3 of each day. let each year equal 365 1/4 days. Determine the number of days in a year the average human sleeps. (p. 314)
121 3/4 days or estimated 120 days
120 1/2 + 40 1/3
160 5/6 Rename 1/2 as 3/6 and 1/3 as 2/6 Add the whole numbers and fractions separately Simplify
7 4/9 + 10 2/9 (page 300)
17 2/3 (estimates to 17)
7 4/9 + 10 2/9 =
17 6/9
Convert 17.22 inches to cm (p. 320)
2.54cm is approx. 1 inch 17.22 is approximately 43. 74 cm
How do you convert between customary and metric units?
You can multiply by fractions to convert between customary and metric units.
Order Rational Numbers (p. 273)
You can order rational numbers using place value. Line up the decimal points and compare.
Least Common Denominator (LCD)
is the LCM or least common multiple of the denominators. You can use the LCD to compare fractions. You can also use a number line.
Methods for adding/subtracting mixed numbers
#1: Rename mixed numbers #2: Write as improper fractions
4/5 x (-6) (p. 317)
- 4 4/5
- 2/3 - 1/2
- 7/6 or - 1 1/6
Find 3/4 divided by (-1/2) (p. 329)
-1 1/2 which approx. to -2
-1/15 + (9/15)
-10/15
-5/8 - 7/8
-2/8
- 3/5 + (-1/5) (p. 284)
-4/5
-3/5 + -1/5
-4/5? (Check notes from Ch 4 lesson 3)
2/3 - 1/2
-4/6 - 3/6 = 1 1/6
-3/4 + (-3/4)
-7 2/4
-5/9 - 2/9
-7/9
Irrational
Does not terminate or repeat Pie
Define: Like Fractions
Fractions that have the same denominator
Terminating decimal
If the repeating digit is zero, the decimal is a terminating decimal. The terminating decimal 0.250000 is typically written as 0.25.
Convert 17.22 in to cm
Known units = 1 in. = 2.54 Unknown units: 17.22in/x cm
Convert 6 yards to meters
Known: 1/.91m Unknown: 6/ x meters .91 x 6 = 5.45
Compare and Order Rational Numbers (10/16 Notes)
Part 1: Compare negative fractions Step 1 1. common denominators 2. number line and place 3. compare Part 2 Ordering Numbers Steps: 1. Convert to decimal 2. carry the place value 3. order
Tips for solving terminating/repeating Decimals
Part 1: Fraction the decimal Steps: Look at place value Put over number reduce Ex: 2.75 = 2 75/100
Rational Numbers
Real number. Terminates of repeats whole numbers integers
Add and Subtract +/- on the number line
Start at first number: 1. add = Turn RIGHT 2. subtract = turn LEFT 3. if there is another negative on the number line, turn 180 degrees and walk.
Repeating decimal
The decimal form of a fraction. They can be represented using bar notation.
How do you divide fractions? (p. 328)
To divide by a fraction, multiply by its multiplicative inverse, or reciprical
Multiply fractions
To multiply fractions, multiply the numerators and multiply the denominators.