- 1). Determine the measurement you have in miles per hour. For an example, convert 30 mph into its equivalent in kilometers per hour.
- 2). Multiply the number in miles per hour by 1.61. The more exact conversion is 1.609, but you can round to two decimal places. For example, 30 multiplied by 1.61 equals 48.3.
- 3). Express your result in kilometers per hour. Therefore, 30 mph converts to 48.1 kph.
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