John invented a new thermometer. He called it X-Therm. John knows that, \(-30^\circ\) X represented the freezing point of water, and \(90^\circ \) X represented the boiling point of water.
One day, John measure a water with his thermometer, for his science essay, it showed \(60^\circ\) X. The problem is, John has to use the International System of Units (SI) for his essay - which is the Kelvin scale. According to the data above, what is \(60^\circ\) X in Kelvin ?
Hint : The Kelvin's freezing point is 273, and the boiling point is 373