Grade 4 - Progress in Mathematics

Subtract Decimals

13-9

9

0 10 10 7 10

1 0.0 5 9.8 0


 8.2 0 
 3.4 2

1.8 5 6.3 8

Black Rock

38.2 km

Sam’s

Beach

18.46 km Beacon

Old Farm

Village

(^39). 05 km
26 km
9 km
25.^3 km
Think
7.54 is close to 10.
The answer is reasonable.
How much farther is it from the
Village to Black Rock than
from Old Farm to Sam’s Beach?
To find how much farther, subtract:
26
18.46
First, round to estimate the
difference: 26
18.46
30
20  10
Then subtract.
Line up the Subtract the Subtract the Regroup.
decimal points. hundredths. tenths. Subtract the
Regroup. ones.
9 9 9 15 9
5 10 10 5 10 10 5 10 10 1 5 10 10

2 6 .0 0
2 6.0 0
2 6.0 0
2 6.0 0

1 8.4 6
1 8.4 6
1 8. 4 6
1 8 .4 6

4
5 4
7 5 4
Remember:
26 26.00 Write the
decimal point
It is 7.54 km farther. in the difference.
Study these examples.
1.212 tenths
0 12
1.2

0.8
0.4
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