Standard Form Practice Questions Corbett - Grade 1 Place Value

Master standard form and place value concepts through these 5 detailed exercises with step-by-step solutions.

Solution: Exercises 1 to 3
1 Standard form conversion
Exercise 1
Write the number in standard form: 3 tens and 5 ones
Definition:

Standard form: Writing a number with digits in their correct place value positions (e.g., 35)

Place value: The value of a digit based on its position in the number (tens, ones, etc.)

Conversion method:
  1. Identify the number of tens and ones
  2. Convert tens to their numerical value (multiply by 10)
  3. Add the ones value
  4. Write the total in standard form
Given
3 tens and 5 ones
Convert
3×10 + 5×1
Standard Form
35
Step 1: Identify place values

We have 3 tens and 5 ones

Step 2: Convert tens to numerical value

3 tens = 3 × 10 = 30

Step 3: Keep ones value

5 ones = 5 × 1 = 5

Step 4: Add values together

30 + 5 = 35

Step 5: Write in standard form

The standard form is 35

3
5
Tens Place
3
Ones Place
5
Expanded Form
35 = 30 + 5 = 3×10 + 5×1
3 tens and 5 ones = 35
Final answer:

The standard form is 35

Applied rules:

• Place value rule: Tens are worth 10 times their digit value

• Standard form: Combine place values to form the complete number

• Digit placement: Tens go in the tens place, ones in the ones place

2 Expanded to standard form
Exercise 2
Write 40 + 7 in standard form
Definition:

Expanded form: Writing a number as the sum of its place values (40 + 7)

Standard form: Writing the number as a whole (47)

Expanded
40 + 7
Addition
47
Standard Form
47
Step 1: Identify expanded form

We have 40 + 7, where 40 represents 4 tens and 7 represents 7 ones

Step 2: Add the values

40 + 7 = 47

Step 3: Identify place values

47 has 4 in the tens place and 7 in the ones place

4
7
Tens Place
4
Ones Place
7
Expanded Form Verification
47 = 40 + 7 = 4×10 + 7×1
40 + 7 = 47
Final answer:

The standard form is 47

Applied rules:

• Expanded form: Shows the value of each digit separately

• Standard form: Combines expanded values into one number

• Addition principle: Sum all place values to get the standard form

3 Word form to standard
Exercise 3
Write "twenty-three" in standard form
Definition:

Word form: Writing numbers using words (twenty-three)

Standard form: Writing numbers using digits (23)

Word Form
twenty-three
Break Down
2 tens and 3 ones
Standard Form
23
Step 1: Understand the word form

"Twenty-three" means twenty (20) plus three (3)

Step 2: Break down into place values

Twenty = 2 tens = 20

Three = 3 ones = 3

Step 3: Add the values

20 + 3 = 23

Step 4: Write in standard form

Place 2 in the tens place and 3 in the ones place

2
3
Tens Place
2
Ones Place
3
Expanded Form Verification
23 = 20 + 3 = 2×10 + 3×1
twenty-three = 23
Final answer:

The standard form is 23

Applied rules:

• Number words: Know the value of number words (twenty = 20, thirty = 30, etc.)

• Place value recognition: Identify tens and ones from word forms

• Standard form conversion: Convert word form to digit form

Rules and methods, laws,...
Standard Form = Tens × 10 + Ones × 1
Standard Form Formula
Standard Form
35
Written with digits
Expanded Form
30 + 5
Value of each place
Word Form
Thirty-five
Written with words
Key definitions:

Standard form: Writing a number using digits in their correct place value positions

Place value: The value of a digit based on its position (tens, ones)

Expanded form: Writing a number as the sum of its place values

Complete methodology:
  1. Identify the given form: Determine if you have word form, expanded form, or place values
  2. Break down place values: Separate tens and ones
  3. Convert to standard form: Use the formula: Tens × 10 + Ones × 1
  4. Verify the result: Check by converting back to another form
Tip 1: Remember: tens are worth 10 times their digit value.
Tip 2: Always write the tens digit first, then the ones digit.
Tip 3: Use expanded form as a bridge between word form and standard form.
Tip 4: Practice counting by tens to strengthen place value understanding.
Common errors: Mixing up tens and ones places, forgetting to multiply tens by 10.
Exam preparation: Master number words up to 100, practice place value identification.
Formulas to know by heart:

• Standard form = Tens × 10 + Ones × 1

• Expanded form = (Tens × 10) + (Ones × 1)

• 1 ten = 10 ones

• Place value positions: tens, ones

Standard Form
24

Written with digits

Expanded Form
20 + 4

Place values added

Word Form
Twenty-four

Written with words

Solution: Exercises 4 to 5
4 Mixed place values
Exercise 4
Write 1 ten and 8 ones in standard form
Definition:

Place value breakdown: 1 ten = 10, 8 ones = 8

Given
1 ten and 8 ones
Convert
1×10 + 8×1
Standard Form
18
Step 1: Identify place values

We have 1 ten and 8 ones

Step 2: Convert tens to numerical value

1 ten = 1 × 10 = 10

Step 3: Keep ones value

8 ones = 8 × 1 = 8

Step 4: Add values together

10 + 8 = 18

Step 5: Write in standard form

Place 1 in the tens place and 8 in the ones place: 18

1
8
Tens Place
1
Ones Place
8
Expanded Form Verification
18 = 10 + 8 = 1×10 + 8×1
1 ten and 8 ones = 18
Final answer:

The standard form is 18

Applied rules:

• Place value rule: Tens are worth 10 times their digit value

• Standard form: Combine place values to form the complete number

• Digit placement: Tens go in the tens place, ones in the ones place

5 Multiple conversions
Exercise 5
Convert "forty-two" to expanded form and then to standard form
Definition:

Word to expanded to standard: A multi-step conversion process

Word Form
forty-two
Expanded Form
40 + 2
Standard Form
42
Step 1: Understand the word form

"Forty-two" means forty (40) plus two (2)

Step 2: Convert to expanded form

Forty = 4 tens = 40

Two = 2 ones = 2

Expanded form: 40 + 2

Step 3: Add to get standard form

40 + 2 = 42

Step 4: Verify place values

42 has 4 in the tens place and 2 in the ones place

4
2
Tens Place
4
Ones Place
2
Expanded Form
42 = 40 + 2 = 4×10 + 2×1
forty-two = 40 + 2 = 42
Final answer:

Expanded form: 40 + 2, Standard form: 42

Applied rules:

• Multi-step conversion: Word form → Expanded form → Standard form

• Number words: Know the value of number words (forty = 40, fifty = 50, etc.)

• Sequential processing: Convert one form to another systematically

Place Value Laws, Methods, Rules, and Definitions
Standard Form = Tens × 10 + Ones × 1
Place Value Formula
Key definitions:

Standard form: Writing a number using digits in their correct place value positions (e.g., 25)

Expanded form: Writing a number as the sum of its place values (e.g., 20 + 5)

Word form: Writing a number using words (e.g., twenty-five)

Place value: The value of a digit based on its position in the number (tens, ones)

Tens place: The second position from the right, representing groups of 10

Ones place: The rightmost position, representing individual units

Complete methodology:
  1. Analyze the given form: Identify whether you have word form, expanded form, or place values
  2. Identify place values: Determine how many tens and ones are represented
  3. Apply conversion rules: Use the standard form formula: Tens × 10 + Ones × 1
  4. Verify the result: Check by converting back to another form or counting
Tip 1: Remember that 1 ten equals 10 ones, which helps with conversions.
Tip 2: Always write tens digit first, followed by the ones digit in standard form.
Tip 3: Use base-10 blocks or drawings to visualize place value concepts.
Tip 4: Practice counting by tens (10, 20, 30...) to strengthen place value understanding.
Tip 5: Read numbers aloud to connect word form with standard form.
Common errors: Confusing tens and ones positions, forgetting that tens represent groups of 10.
Key insight: Every two-digit number can be broken down into tens and ones.
Memorization aid: "Tens come first, then ones" - the order matters in standard form.
Essential laws and formulas:

• Standard form = (Tens digit × 10) + (Ones digit × 1)

• Expanded form = (Tens value) + (Ones value)

• 1 ten = 10 ones (conversion factor)

• In standard form, the leftmost digit is in the tens place

• In standard form, the rightmost digit is in the ones place

Examples
12 = 10 + 2

1 ten and 2 ones

Examples
34 = 30 + 4

3 tens and 4 ones

Examples
56 = 50 + 6

5 tens and 6 ones

Problem-solving strategies:
  1. Visual representation: Draw tens sticks and ones dots to represent numbers
  2. Base-10 model: Think of tens as groups of 10 individual units
  3. Counting strategy: Count by tens first, then count additional ones
  4. Verification method: After finding standard form, break it back into tens and ones to check

Questions & Answers

Question: I'm confused about why we write 3 tens and 5 ones as 35 instead of 53. Why does the 3 come first?

Answer: Great question! This is about place value order. In our number system, we always write the largest place value first:

  • The tens place is always on the left because it represents the larger value (3 tens = 30)
  • The ones place is always on the right because it represents the smaller value (5 ones = 5)

Think of it like this: in the number 35, the 3 tells us how many tens we have (30), and the 5 tells us how many extra ones we have (5). So 35 means 30 + 5.

If we wrote 53, that would mean 5 tens (50) and 3 ones (3), which equals 53 total - a completely different number!

Remember: Tens come first, then ones in standard form!

Question: My child is struggling to convert "seventeen" to standard form. How can I help them understand this better?

Answer: Breaking down number words can help! Here's a step-by-step approach:

  1. Listen to the word: "Seventeen" sounds like "seven-teen"
  2. Recognize the pattern: Numbers ending in "-teen" mean ten plus that number
  3. Break it down: Seventeen = seven + ten = 7 + 10 = 17
  4. Identify place values: One ten and seven ones
  5. Write in standard form: 1 in the tens place, 7 in the ones place = 17

Visual aids help too: use 1 group of 10 objects and 7 individual objects to show "seventeen" visually.

Practice with other teen numbers: fourteen (14), fifteen (15), sixteen (16), etc. to reinforce the pattern!

Question: What happens when I have 10 ones? Do I still write it in the ones place?

Answer: Excellent observation! When you have 10 or more ones, something special happens:

  • 10 ones = 1 ten - this is a fundamental place value rule
  • When you have 10 ones, you "trade" them for 1 ten
  • This 1 ten gets placed in the tens column

For example, if you had 2 tens and 10 ones:

• You'd trade the 10 ones for 1 ten

• Now you have 2 tens + 1 ten = 3 tens, and 0 ones left over

• The standard form would be 30

This is called "regrouping" and it's how our base-10 number system works!