Warm-Up (9/30)
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Transcript Warm-Up (9/30)
Notes 7.2B Decimal Operations
Adding Decimals
*Line the decimals up!
EX:
2.345
+ 13.41
Answer: 15.755
Rewrite:
Subtracting Decimals
*Line up the decimals!
EX:
11.428
+ 8.67
Answer: 2.758
Rewrite:
Multiplying Decimals
*Put the number with most digits on top and line up
LAST numbers
Move the decimal back at the end
EX:
x
Answer:
2.345
13.4
31.423
Rewrite:
Dividing Decimals
*Kick the ball to the wall
Do the same in the hall
& Throw it on the roof
EX:
÷
Answer:
25.7
3.1
8.290
Rewrite:
7.2B Fraction Operations
Adding Fractions
*we must first find a COMMON
DENOMINATOR
• Then add the numerators
Rewrite (w/ common denominators):
EX:
2 ¾ +5 ½
Subtracting Fractions
*we must first find a COMMON
DENOMINATOR
• Then subtract the numerators
EX:
Rewrite (w/ common denominators):
4 1/3 - 3 ½
Multiplying Fractions
• Multiply numerator times numerator to get our
numerator
• And multiply denominator times denominator
to get our denominator
Mixed Numbers:
1
3
1
3
X
2
X
8
3
Need to make
an improper
fraction then
multiply
2
3
=
8
9
Improper Fraction – bigger numerator than
denominator
Dividing Fractions
•
If dividing fractions Keep the first fraction Flip
the second (reciprocal) and Change the sign (KFC)
1 ÷ 2
3
5
=
1 X 5
3
2
reciprocal
=
5
6
Dividing Mixed Numbers:
1 ÷
4
1
3
2 =
1
3
X
4
7
1 ÷ 7
4
3
=
3
28
=
Practice Questions
On your own sheet of notebook paper please
complete the following problems:
p 293 #20-28 (odds) p 304 #39-47(odds)
p 316 #15-19(odds), 21-25(odds)
Book Practice
On a separate sheet of paper please do the
following questions in your book:
(and please show your work)
Page 137 #25-30
Page 150 #26-30
Page 713 #16-20