Estimating Products

Round 354 to the
nearest hundred

Multiple Choice

What does it mean to estimate?

• To make an educated guess

• To give an exact answer

We can use estimating to solve 3 x 165. If I round to the nearest hundred, this will be easier to solve!

Step 1: Round the
bigger number to the nearest hundred.

3 x 165

3 x 200

3 x 165

Step 2:

Think: 3 x 200

1.

Figure out your basic
fact: 3 x 2 = 6

2.

Count the number of zeros in your bigger number -- 200 has 2 zeros!

3.

Add that to your answer

4.

SO…. 3 x 200 = 600

Step 1: Round the
bigger number to the nearest ten.

4 x 86

4 x 90

4 x 86

Step 2:

Think: 4 x 90

1.

Figure out your basic
fact: 4 x 9 = 36

2.

Count the number of zeros in your bigger number -- 90 has 1 zero!

3.

Add that to your answer

4.

SO…. 4 x 90 = 360

Step 1: Round the
bigger number to the nearest thousand.

4 x 2,621

4 x 3,000

4 x 2,621

Step 2:

Think: 4 x 3,000

1.

Figure out your basic
fact: 4 x 3 = 12

2.

Count the number of
zeros in your bigger
number -- 3,000 has 3 zeros!

3.

Add that to your answer

4.

SO... 4 x 3,000 = 12,000

​YOUR TURN!!

Use estimating to find

6 x 316

Use estimating to find

5 x 29

Use estimating to find

5 x 2,213

Use estimating to find

6 x 4,113

Use estimating to find

7 x 473