To convert 80 miles per hour to kilometers per hour, you can use the conversion factor that 1 mile is equal to 1.60934 kilometers. Here are the step-by-step instructions to perform the conversion:

Step 1: Write down the given value, which is 80 miles per hour.

Step 2: Multiply the given value by the conversion factor of 1.60934 kilometers per mile. This is done to cancel out the miles and convert them to kilometers. The conversion factor is derived from the fact that 1 mile is equal to 1.60934 kilometers.

80 miles/hour * 1.60934 kilometers/mile = 128.7472 kilometers/hour

Step 3: Round the result to an appropriate number of decimal places. In this case, let’s round it to two decimal places.

128.7472 kilometers/hour ≈ 128.75 kilometers/hour

Therefore, 80 miles per hour is approximately equal to 128.75 kilometers per hour.