<h4>Enter Your marks out of 600</h4>
<input type="number" max="600" min="0" onInput="caliculatePercent(this.value)">
<p></p>
// Scales with continuous input and continuous output
const heighestMarks = 600
let scale = d3.scaleLinear()
              // Provide the range of values  
              .domain([0,heighestMarks])
              // Provide range of output need
              .range([0,100])

function caliculatePercent(value){ 
  d3.select("p")
    .text(`Your Percentage is ${scale(value)}%`)
}

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