Grade 4 - Progress in Mathematics

Subtract with Regrouping

3-6

h t o

8 5 8


7 4 9

h t o

4 18

8 5 8


7 4 9

9

h t o

4 18

8 5 8


7 4 9

0 9

h t o

4 18

8 5 8


7 4 9

1 0 9

Height of Tall Buildings

in Los Angeles, California

U.S. Bank To w e r 1018 feet

Aon Center 858 feet

Gas Company To w e r 749 feet

Arco Center 735 feet

Wells Fargo To w e r 723 feet

United California Bank Plaza 717 feet

How much taller is the

Aon Center than the

Gas Company Tower?

To find how much taller,

subtract: 858 
749.

First, use rounding to estimate:

900 
 700 200. Then subtract.

See if there are More ones are needed. Subtract the ones.

enough ones Regroup the tens to

to subtract. get more ones.

58 5 tens 8 ones

 4 tens 18 ones

Subtract the tens. Subtract the hundreds. Check by adding.

1

1 0 9

 7 4 9

8 5 8

The Aon Center is 109 feet taller.

Study these examples.

6 14 7 13 5 11

7 4 $ 8. 3 8 6 1 2


 4 6 
 7.9 5 
 9 1

2 8 $. 4 3 5 2 1

Think

109 is close to 200.

The answer is reasonable.

3.1

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