The arithmetic operation involving Addition, Subtraction, Multiplication and Division can be demonstrated using a number line. On a number line Positive and Negative numbers are marked on either side with zero in the middle. To mark a positive integer, starting from 0 the counting is done towards the right and for a negative integer towards the left.

**Addition**Add 1 + 4 on a Number line.

1 is marked starting from zero and moving one unit towards the right. As 4 a positive quantity is added, four units are counted from 1 towards the right landing on 5. For adding a negative quantity the move is made towards the left.

**Subtraction**Subtract 7 from 5

Subtracting a number is same as adding its additive inverse. Subtracting 7 is equivalent to adding -7.Starting from 5, seven units are moved towards the left to get the answer as -2.

**Skip Counting:**
The number line can be used for skip counting to get a sequence of numbers with equal difference between two consecutive numbers. The diagram illustrates how odd numbers are counted skipping two.

**Multiplication**Multiplication is nothing but repeated addition. This operation is done on a number line using the method of skip counting.

**Division **Just as multiplication is repeated addition, division is repeated subtraction. Starting from the dividend, the divisor is skip counted towards the left. The counting is stopped when a number less than the divisor is reached. The number of skips gives the quotient while the number where the counting stops is the remainder.