Transcript Notes Over 3 – 1 - Coweta County Schools

Notes Over 3 – 1
Round each number to the given place value.
1. Round 8.7398
7
to the nearest:
a. tenth
Since the 3 in the
hundredths place is
lower than 5, the 7 in
the tenths place stays
a 7. Drop everything
past the 7.
8.7
Notes Over 3 – 1
Round each number to the given place value.
1. Round 8.7398
to the nearest:
8
a. tenth
b. integer
Since the 3 in the
hundredths place is
lower than 5, the 7 in
the tenths place stays
a 7. Drop everything
past the 7.
8.7
Since the 7 in the
tenths place is higher
than 5, the 8 in the
ones place becomes a
9. Drop everything past
the decimal.
9
Notes Over 3 – 1
Round each number to the given place value.
2. Round 7,098.56
0
to the nearest:
a. hundred
Since the 9 in the tens
place is higher than 5,
the 0 in the hundreds
place becomes a 1.
Everything behind the 1
becomes a 0 up to the
decimal.
7,100
Notes Over 3 – 1
Round each number to the given place value.
5 to the nearest:
2. Round 7,098.56
a. hundred
b. tenth
Since the 9 in the tens Since the 6 in the
place is higher than 5, hundredths place is
the 0 in the hundreds higher than 5, the 5 in
place becomes a 1.
the tenths place
Everything behind the 1 becomes a 6. Drop
becomes a 0 up to the everything past the 5.
decimal.
7,100
7,098.6
Notes Over 3 – 1
3. Estimate by Rounding.
a. $4.89 $5
+ $3.87 + $4
$9
b. 453.56 450
- 230.07 - 230
220
Notes Over 3 – 1
4. Estimate by Front-End Estimation.
a. 114.39
4
+ 779.102 + 9
+ 13 = 93
80
.3
b. 22.298
+ 77.750 + .8
+ 1.1 = 10.1
9
Notes Over 3 – 1
5. Estimate by Clustering.
a. $4.50 + $5.20 + $5.55
Since all of them are close to $5, you can
multiply:
$5 X 3 = $15
b. 26.7 + 26.2 + 24.52 + 25.25 +23.9
Since all of them are close to 25, you can
multiply:
25 X 5 = 125
Notes Over 3 – 2
.
6.43 4.7
6 . 5 = 30
1. Estimate by Rounding.
Notes Over 3 – 2
2. Joshua bought 3 yards of fabric
to make a dress. The fabric cost
$5.65/yd. The clerk said his total
was $14.95 before tax. Did the
clerk make a mistake? Explain.
5.65 . 3
6 . 3 = 18
5 . 3 = 15
It should have
cost between $15
and $18.
Notes Over 3 – 2
..
..
Estimate by using Compatible Numbers.
3. 38.9
38
4.
.
82.52 .
.
84 .
1.79
2 = 19
4.25
4 = 21
Notes Over 3 – 2
5. Is 3.29 a reasonable quotient for
31.423 5.94? Explain.
30

..
6 =5
It should have
been closer to 5.
Page 125, 3 – 1 #1-13, 14-46 even
Page 129, 3 – 2 #1-8, 10-30 even