Step-by-step Maths Level 2: Tens and ones in a number
Part of the Step-by-step Maths Level 2 tens and ones chapter. Chapter overview · whole chapter on one page
Tens and ones in a number
Every 2-digit number has a tens digit and a ones digit.
In 47, the 4 means 4 tens, which is 40. The 7 means 7 ones.
Key ideas
- The left digit is the tens.
- The right digit is the ones.
- 47 is 4 tens and 7 ones.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.4 tens
- Look at the second digit. It is the number of ones.7 ones
- Write the answer. Say the tens, then the ones.4 tens and 7 ones
Check. 4 tens is 40, and 40 + 7 = 47.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.9 tens
- Look at the second digit. It is the number of ones.0 ones
- Write the answer. Say the tens, then the ones.9 tens and 0 ones
Check. 9 tens is 90, and 90 + 0 = 90.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.6 tens
- Look at the second digit. It is the number of ones.2 ones
- Write the answer. Say the tens, then the ones.6 tens and 2 ones
Check. 6 tens is 60, and 60 + 2 = 62.
Watch out. Read the digits from left to right. The left digit is the tens.
Watch out
Watch out. In 47 the 4 is worth 40, not 4. Position matters.
Exam tip
Grown-up tip. Write numbers on a place value grid with columns for tens and ones. Ask: “How many tens?” first.
Exercise 2B Practice: tens and ones in a number
Non-calculatorMethod. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.1 tens
- Look at the second digit. It is the number of ones.2 ones
- Write the answer. Say the tens, then the ones.1 tens and 2 ones
Check. 1 tens is 10, and 10 + 2 = 12.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.5 tens
- Look at the second digit. It is the number of ones.9 ones
- Write the answer. Say the tens, then the ones.5 tens and 9 ones
Check. 5 tens is 50, and 50 + 9 = 59.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.6 tens
- Look at the second digit. It is the number of ones.9 ones
- Write the answer. Say the tens, then the ones.6 tens and 9 ones
Check. 6 tens is 60, and 60 + 9 = 69.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.5 tens
- Look at the second digit. It is the number of ones.6 ones
- Write the answer. Say the tens, then the ones.5 tens and 6 ones
Check. 5 tens is 50, and 50 + 6 = 56.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.7 tens
- Look at the second digit. It is the number of ones.4 ones
- Write the answer. Say the tens, then the ones.7 tens and 4 ones
Check. 7 tens is 70, and 70 + 4 = 74.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.9 tens
- Look at the second digit. It is the number of ones.4 ones
- Write the answer. Say the tens, then the ones.9 tens and 4 ones
Check. 9 tens is 90, and 90 + 4 = 94.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.1 tens
- Look at the second digit. It is the number of ones.5 ones
- Write the answer. Say the tens, then the ones.1 tens and 5 ones
Check. 1 tens is 10, and 10 + 5 = 15.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.9 tens
- Look at the second digit. It is the number of ones.7 ones
- Write the answer. Say the tens, then the ones.9 tens and 7 ones
Check. 9 tens is 90, and 90 + 7 = 97.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.7 tens
- Look at the second digit. It is the number of ones.0 ones
- Write the answer. Say the tens, then the ones.7 tens and 0 ones
Check. 7 tens is 70, and 70 + 0 = 70.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.4 tens
- Look at the second digit. It is the number of ones.7 ones
- Write the answer. Say the tens, then the ones.4 tens and 7 ones
Check. 4 tens is 40, and 40 + 7 = 47.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.9 tens
- Look at the second digit. It is the number of ones.9 ones
- Write the answer. Say the tens, then the ones.9 tens and 9 ones
Check. 9 tens is 90, and 90 + 9 = 99.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.8 tens
- Look at the second digit. It is the number of ones.5 ones
- Write the answer. Say the tens, then the ones.8 tens and 5 ones
Check. 8 tens is 80, and 80 + 5 = 85.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.8 tens
- Look at the second digit. It is the number of ones.2 ones
- Write the answer. Say the tens, then the ones.8 tens and 2 ones
Check. 8 tens is 80, and 80 + 2 = 82.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.2 tens
- Look at the second digit. It is the number of ones.3 ones
- Write the answer. Say the tens, then the ones.2 tens and 3 ones
Check. 2 tens is 20, and 20 + 3 = 23.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.1 tens
- Look at the second digit. It is the number of ones.8 ones
- Write the answer. Say the tens, then the ones.1 tens and 8 ones
Check. 1 tens is 10, and 10 + 8 = 18.
Watch out. Read the digits from left to right. The left digit is the tens.
Method. The tens digit tells us the tens. The ones digit tells us the ones.
- Look at the first digit. It is the number of tens.7 tens
- Look at the second digit. It is the number of ones.1 ones
- Write the answer. Say the tens, then the ones.7 tens and 1 ones
Check. 7 tens is 70, and 70 + 1 = 71.
Watch out. Read the digits from left to right. The left digit is the tens.