Whole numbers

• Use place value to compare and order whole numbers.
• Numbers lined up by place value and written one underneath the other can be added or subtracted.
• Times table skills are useful when multiplying and dividing whole numbers.

Refresh your knowledge with these guides on place value and calculations with whole numbers.

To write a whole number in words:

1. Use commas to split the number into groups of three digits from right to left.
2. Read the number from left to right:
   • Read each set of three digits, followed by the place value name of the group of digits.

To write a whole number in figures:

1. Write each separately named number.
2. Add up the numbers.

Follow the working out below

GCSE exam-style questions

Whole numbers are ordered using place value.

• Ascending order means start with the smallest value.
• Descending order means start with the largest value.

To order whole numbers:

1. Write the numbers one underneath the other, lining up the units place value digits.
2. Start on the left to compare digits.
   • The greater the digit, the larger the number.
   • If the digits are equal, move one place to the right and compare digits again.

Inequality symbols (< >) are used to show whether a number is greater or smaller than another:

• > means greater than.
• < means less than.

Follow the working out below

GCSE exam-style questions

To add whole numbers using the column method:

1. Write the numbers in a vertical list, lining up the unit digits.
2. Start on the right-hand side, the unit column. Add the digits in the column.
   • If the total is less than 10, write the digit in the answer space.
   • If the total is 10 or more, write the units digit in the answer space for the column and carry the tens digit to the next column on the left.
3. Move left to the next place value column. Add the digits in the column and add any digit that was carried to this column.
4. Repeat the addition process in each column until the calculation is complete.

Follow the working out below

To subtract whole numbers using the column method:

1. Write the larger number above the smaller number in a vertical list, lining up the unit digits.
   • Column subtraction works from right to left.
2. Start with the unit column on the right-hand side, subtract the bottom digit from the top digit, write the answer in the answer space.
3. Move left to the next column.
4. Complete the subtraction process for each column until the calculation is complete.

If the top digit is smaller than the bottom digit, regroup the number.

Follow the working out below

GCSE exam-style questions

Long multiplication may be written using the grid method or the column method.

To multiply whole numbers using the grid method:

1. To multiply a 3-digit number by a 2-digit number use a 2 × 3 grid.
2. Label the sides of the grid with the place value of the digits in the numbers.
3. Work out the product of the place values for each cell.
4. Add the products in the cells to complete the calculation.

To multiply whole numbers using the column method:

1. Write the numbers vertically lining up the unit digits.
2. Multiply the top number by the unit digit of the bottom number working right to left.
   • Write the answers in the first row of the working space.
3. Write a zero in the unit position on the second row of the working space to show the number has been multiplied by ten.
4. Multiply the top number by the tens digit of the bottom number.
   • Write the answers in the second row of the working space.
5. Add the working answers to complete the calculation.

Different methods of multiplication may be used. Refresh your knowledge of Napier’s method, the area/grid method and short multiplication.

Follow the working out below

To divide whole numbers using short division (sometimes called the bus stop method):

1. Write the question in bus stop form:
   • The dividing digit is the divisor and goes outside the bus stop.
   • The dividend goes inside the bus stop.
   • The answer (quotient) will be written on the top of the bus stop.
2. Work from left to right dividing each digit in turn.
3. If there is a remainder, it becomes the tens digit for the next division.

Follow the working out below

GCSE exam-style questions

Practise what you've learned about whole numbers with this quiz. The questions change each time you try, so keep testing your knowledge.

Now you've revised whole numbers, why not learn about how to round numbers?