Math – Review & Practice

Place Value

What are digits?

Digits are the numbers…

Together, they can be combined to make up all of the numbers.

What is place value?

Place value is the value given to the place a digit has in a number.

For example: Look at the number 3,056.

The 5 is in the ten’s place, so it’s value equals 50.

You try! Look at the number 14,289.

What is the value of the underlined digit?

The 4 is in the thousands place, so the value is 4,000.

What is the value of the underlined digit?

1. 14,768

2. 256,201

3. 134,783

4. 845,682

5. 614,503

6. 1,234,568,245

700

1

30,000

5,000

600,000

200,000,000

What is a period in math?

A period is a group of three digits in a number, separated by a comma.

Ones PeriodThousands Period

Get a pencil and write the numbers below in standard form.

Two hundred four million, one hundred one

40,000,000 + 30,000 + 200 + 8

Write the numbers below in expanded form.

1. One thousand, two hundred twenty-five

2. 543,031

3. Fifty billion, two hundred eight

Write the word name for the numbers below.

1. 25,658,012,041

Twenty-five billion, six hundred fifty-eight million, twelve thousand, forty-one

2. 237,984.02

Two hundred thirty-seven thousand, nine hundred eighty-four and two hundredths

Place Value Relationships

Place Value Relationships

Place Value Relationships

Place Value Relationships

Place Value Relationships

Place Value Relationships

Comparing Numbers

What does it mean to compare?

You are deciding which of 2 numbers is greater.

Step 1: Check to see if there are the same number of digits.

The first number has 5 digits.The second number has 4 digits.

Step 2: If not, the number with more digits has a greater value.

5 digits > 4 digits

So, 28,462 > 2,846 Or, 2,846 < 28,462

Comparing Numbers

What does it mean to compare?

You are deciding which of 2 numbers is greater.

Step 1: Begin at the left if there are the same number of digits. Compare.

Both numbers have an 8 in the thousands place.Both numbers have a 1 in the hundreds place.

Step 2: Find the 1st place the digits differ. Compare.

9 tens > 8 tens

So, 8,193 > 8,186 Or, 8,186 < 8,193

You try it! Compare.

1. 456 465

2. 54,193 54,183

3. 125 152

4. 167,465 167,465

Ordering Numbers

What does it mean to order numbers?You are placing the numbers from least to greatest or greatest to least.

Exploring Rounding

1. What does estimate mean?

It means to find a number close to the exact number.

2. What does rounding mean?

It means replacing a number with a number that tells about how many or how much. (Rounding is a way to estimate.)

Round 56 to the nearest ten.

56 When I count by tens, 56 is between 50 and 60.

So, my answer is either 50 or 60.

56 is closer to 60, so my answer is 60.

Round 35 to the nearest ten.

35 When I count by tens, 35 is between 30 and 40.

So, my answer is either 30 or 40.

35 is halfway to 40, so my answer is 40.

Round 517 to the nearest hundred.

517 When I count by hundreds, 517 is between 500 and 600.

So, my answer is either 500 or 600.

517 is closer to 500, so my answer is 500.

Round 968 to the nearest hundred.

968 When I count by hundreds, 968 is between 900 and 1,000.

So, my answer is either 900 or 1,000.

968 is closer to 1,000, so my answer is 1,000.