Name: __________________________________
Mrs. Sperling/Math 6
Unit 3 Fractions in Simplest Form and
Greatest Common Factor:
Ladder Method
Objective: to learn to express (name) fractions in simplest form.
Fraction: A number describing part of a whole when the whole is cut into
equal pieces.
Denominator: the bottom number in a fraction; it tells how many equal
parts one whole is divided into.
Numerator: The top number in a fraction; it tells how many parts you have
or are talking about.
Equivalent Fractions: Two fractions naming the same amount.
Simplest Form: the name used when the greatest common factor of the
numerator and denominator is the factor of “1.”
Greatest Common Factor: the largest whole number which evenly divides
both the numerator and the denominator.
Enter: The Ladder Method, Day 2
1. WRITE the two numbers
on one line.
2. DRAW THE L SHAPE.
3. DIVIDE out common
factors (recommend prime
2
24
2
12
18
3
6
9
2
3
factors starting with the smallest).
4. LCM makes an L: 2
X
2
X
36
3 X 2 X 3 = 72
5. GCF is down the left side: 2
X
2 X 3 = 12
6. Simplest fraction is on the bottom.
𝟐𝟒
𝟑𝟔
=
𝟐
𝟑
Let’s try one together: Find the GCF and write this fraction in its simplest
12
form:
96
1. WRITE the two
numbers on one line, making sure
the numerator is on the left and
the denominator is on the right.
2. DRAW THE L SHAPE.
3.
DIVIDE out common
factors (recommend prime factors - starting
with the smallest).
4.
GCF is the product of the numbers on the left side.
5.
Simplified fraction is on the bottom:
GCF =
YOU GOT THIS:
a) Find the GCF and write this fraction in its simplest form:
45
75
1. WRITE the two
numbers on one line, making sure
the numerator is on the left and
the denominator is on the right.
2. DRAW THE L SHAPE.
3. DIVIDE out common
factors(recommend prime factors- starting
with the smallest).
4. GCF is the product of the numbers on the left side.
GCF =
5. Simplified fraction is on the bottom:
b) Find the GCF and write this fraction in its simplest form:
240
280
1. WRITE the two
numbers on one line, making sure
the numerator is on the left and
the denominator is on the right.
2. DRAW THE L SHAPE.
3. DIVIDE out common
factor (recommend prime factors-starting
with the smallest).
4. GCF is the product of the numbers on the left side
5. Simplified fraction is on the bottom:
GCF =
YOU GOT THIS: Find the LCM of the given numbers.
12, 18
36, 60
10, 12, 15
32, 40
Name: ______________________________________________________
Applying the LCM
You have learned how to calculate and identify the LCM of two or more numbers. Now
you will apply your knowledge to real world scenarios.
LCM: Key Words
1.
Two faucets are dripping. One drips every 4 seconds and the other drips every
22 seconds. If a drop of water falls from both faucets at the same time, how
many seconds will it be before you see the faucets drip at the same time?
2. A radio station is having a promotion in which every 12th caller receives a free
concert ticket and every 15th caller receives a limo ride. Which caller will be the
first one to win both?
3.
Jenny wears her brown shoes every 4 day. She wears her favorite jeans every 8
days. She wears her Medfield Warrior’s shirt every 6 days. If she last wore her
brown shoes, favorite jeans, and Medfield Warrior’s shirt today, what will the
date be when she wears all three again?
4. Gary made 70 treat bags for his Halloween party. In every 3rd bag he put
lollipops, in every 15th bag he put Hershey Kisses and in every 5th bag he put
fake eyeballs. How many of the 70 bags have all three items in them?