Step 1: Understand the conversion ratio

Before converting units, it is important to understand the conversion ratio between the two units. In this case, 1 cm is equal to 0.393701 inches. This means that for every 1 centimeter, there are 0.393701 inches.

Step 2: Write down the given value

In this case, the given value is 30 cm. Write this down on a piece of paper or in your calculator.

Step 3: Set up the conversion equation

To convert cm to inches, we will use the conversion ratio mentioned earlier. The equation will look like this:

30 cm * 0.393701 in/cm = x in

The “x” represents the unknown value we are trying to find.

Step 4: Cancel out units

We can cancel out the unit of cm from both sides of the equation, leaving us with:

30 * 0.393701 in = x in

Step 5: Multiply to find the value of x

Now, we can simply multiply 30 and 0.393701 to find the value of x. This will give us:

11.81103 in = x in

Note: It is always a good idea to do a rough estimate of the answer to check if it makes sense. In this case, since we are converting from a smaller unit (cm) to a larger unit (in), the answer of 11.81103 in seems reasonable.

Step 6: Round off the answer (optional)

Finally, if necessary, round off the answer to the desired number of decimal places. In this case, let’s round off the answer to two decimal places, giving us the final answer of 11.81 in.

Step 7: Write the final answer

Therefore, 30 cm is equal to 11.81 in. You have successfully converted 30 cm to inches!

Note: You can use the same method to convert any unit of length, as long as you know the conversion ratio.