Grade 4 - Progress in Mathematics

Multiply with Three-Digit Numbers

4-14

Letisha, Marc, Robin, and Tim

all made beaded wall hangings.

How many beads did Robin use?

To find how many,

multiply: 64 
 225

First, use rounding

to estimate: 64 
 225

225 200


 64 
 60

about 12,000

Then multiply.

Multiply by Multiply by Add the

the ones. the tens. partial products.

1 3 1 3

1 2 1 2 1 2

2 2 5 2 2 5 2 2 5


 6 4 
 6 4 
 6 4

9 0 0 9 0 0 9 0 0

1 3 5 0 1 3 5 0

1 4 , 4 0 0

Robin used 14,400 beads.

Study these examples.

6 4

4 2

3 0 9 1 3 2 $ 6. 5 1


 7 5 
 3 1 
 8 4

1 5 4 5 1 3 2 2 6 0 4

2 1 6 3 0 3 9 6 0 5 2 0 8 0

2 3 , 1 7 5 4 0 9 2 $ 5 4 6. 8 4

Beads in

Rows Each Row

Tim 35 528

Marc 44 286

Letisha 56 374

Robin 64 225

Think

14,400 is close to

12,000. The answer

is reasonable.

4 
 225 60 
 225

3.3

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