Grade 4 - Progress in Mathematics

Multiply Three-Digit Numbers

4-7

Each of the 8 families on Pine Road

receives a newspaper delivery each day

of the year. How many newspapers are

delivered on Pine Road each year?

To find how many, multiply: 8 
 365

First, estimate using

front-end digits: 8 
 365

8 
 300  2400

Then multiply.

Multiply the ones. Multiply the tens. Add the

Regroup. regrouped tens. Regroup.

4 5 4

3 6 5 3 6 5


 8 
 8

0 2 0

8 
5 ones 40 ones 8 
6 tens 48 tens

40 ones  4 tens 0 ones 48 tens 4 tens 52 tens

52 tens  5 hundreds 2 tens

Multiply the hundreds. Add the regrouped hundreds.

5 4

3 6 5


 8

2 9 2 0

Each year, 2920 newspapers

are delivered on Pine Road.

8 
3 hundreds 24 hundreds

24 hundreds 5 hundreds 29 hundreds

29 hundreds  2 thousands 9 hundreds

Think

2920 is close to 2400.

The answer is reasonable.

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