Agenda March 24, 2009 (Week 11)
Take your folder, remove your homework.
Write the submitted
homework number on the
inside cover with your new homework
Section 3-5 Fractions
and Decimals, and the
volume of a Sphere
Section 3-6 Square
Roots and Pythagorean
Theorem
Reminder: bring
notebook everyday to this class
3-5 Fractions and Decimals, and the Volume of a Sphere
Objective:
Convert fractions to decimals
Convert decimals to
fractions
Simplify expressions
containing fractions and
decimals
Solve applications
involving fractions and decimals
Converting fractions
to decimals
Examples: Write ¾, 3/5
as decimal
Examples: repeated
decimals 11/12, 5/11
Converting decimals to
fractions
Examples: write 0.38,
0.48, 0.75, 0.025, 12.8 as a fraction in
lowest terms
Examples: write 15.6,
and 12.8 as a mixed number
Problems involving both Fractions and Decimals
Simplify
(19/50)(1.32+0.48)
Simplify
(14/25)(2.43+0.27)
Simplify 1/4 +
(0.25)(3/5)
Simplify
(1/2)3(2.4)+(1/4)2(3.2)
Applications:
If a shirt that
normally sells for $27.99 is on sale for 1/3 off, what
is the sale price of the shirt?
Find the area of a
triangular stamp with base 2 and 5/8 inches,
and height = 1 and ¼ inches.
The volume of a sphere
is (4/3)π(radius)3
= (4/3)πr3
A figure is composed
of a right circular cylinder with half
a sphere on top. (a half-sphere is called a hemisphere)
find the volume of this figure with radius = 5 inches,
height = 10 inches, round to the nearest tenth
Guided Practices and Homework # 22
To
convert fractions to decimals, do we multiply or divide
the numerator by the denominator?
The decimal 0.13 is
equivalent to what fractions?
Write 36 thousandths
in decimal form and in fraction
form
Explain how to write
the fraction 84/1,000 in lowest terms.
Homework # 22, pp
265-270, #1-7 odd, 9-49 EOO, 51-
87 EOO.
3.6 Square Roots and the Pythagorean Theorem
Objective: Find square
roots of numbers
Use decimals to
approximate square roots
Solve problems with
the Pythagorean Theorem
Definition: if b2=
a, then
, and is read as b is the
square root of a. The symbol is called radical symbol,
and a is called radicand.
Examples of square
roots on the board.
Simplify a radical
expression means to remove perfect
square from the radicand
Examples of
simplifying the radical expression on the
board and approximations
Facts from Geometry: The Pythagorean Theorem
A right triangle is a
triangle that contains a 90°(or right)
angle. The longest side in a right triangle is called the
hypotenuse, we use the letter c to denote it. The two
shorter sides are denoted by the letter a and b (they are
called legs)
The Pythagorean
Theorem stated that c2= a2
+ b2
Applications of
Pythagorean Theorem, examples on
the board
A ladder is leaning
against the top of a 6-foot wall. If the
bottom of the ladder is 8 feet from the wall. How long is
the ladder?
Example of Spiral of
roots
8Guided Practices and Homework # 23
Which number is
larger, the square of 10 or the
square root of 10?
Give a definition for
the square root of a number?
What two numbers will
the square root of 20 fall
between?
What is the
Pythagorean Theorem?
Homework #23, page
277-282, # 1-39, # 41-45
ODD, # 47-63 EOO, 67-75 ODD