How to calculate distance ratio with momentjs and turfjs

Hello,
With JS anf turfjs library I need on several markers calculate
1) medium speed
2) time of arrival at any marker point

I make as:

    const markerIds = Object.keys(markers)
    const points2Data = []

    let summarized_distance= 0
    let arrival_date= moment(tripRow.arrival_date)// arrival time
    let departure_date= moment(tripRow.departure_date) // departure time

    for (let i = 1; i < markerIds.length; i++) {
      const marker = markers[markerIds[i - 1]]

      const nextMarker = markers[markerIds[i]]
      const from = turf.point([marker.lat, marker.lng])
      const to = turf.point([nextMarker.lat, nextMarker.lng])
      const distance = turf.distance(from, to, { units: 'kilometers' })
      summarized_distance= summarized_distance + distance
      // get data
      const points2Item = {
        id: marker.id,
        start: marker.id,
        end: nextMarker.id,
        speed: marker.speed,
        lat: nextMarker.lat,
        lng: nextMarker.lng,
        latlng: [nextMarker.lat, nextMarker.lng],
        distance: distance,
        time: distance / marker.speed,
        eta:null

      }

      points2Data.push(points2Item)
    } // for (let i = 1; i < markerIds.length; i++) {

    // get medium speed
    let calculated_speed = summarized_distance / summarized_trip_time


    let next_arrival_time= arrival_date
    for (let i = 0; i < points2Data.length; i++) {

        // I think I need to get raio of 1 marker distance  from whole distance
      let distance_ratio= summarized_distance / points2Data[i].distance

      // I think I need to get calculate time ratio and add it to next_arrival_time, something like
      next_arrival_time= next_arrival_time.add(CALCULATED_RATIO_TIME, 'hour')
      // But how to calculate this CALCULATED_RATIO_TIME ?
      points2Data[i].eta= next_arrival_time.format('YYYY-MM-DD HH:mm')

Code (JavaScript):

how to calculate this CALCULATED_RATIO_TIME ?

I hope my common flow is correct, but I encountered this issue...
Thanks!

 

I remade it as :

    let next_arrival_time= departure_date
    for (let i = 0; i < points2Data.length; i++) {

      // That was invalid  I got ratio of distance
      let distance_ratio= points2Data[i].distance / summarized_distance
    
      // I got ratio of time
      next_arrival_time= next_arrival_time.add( summarized_trip_time * distance_ratio   , 'hour')

      points2Data[i].eta= next_arrival_time.format('YYYY-MM-DD HH:mm')

    } // for (let i = 1; i < points2Data.length; i++) {

Code (JavaScript):

Lokking at results I have results very similar as I expect,
but havinf
departure_date= ‘2020-03-02 12:00:00’
and
arrival_date='2020-03-03 12:00:00'

with several points I got last point :
2020-03-03 11:59
and I lost 1 minutes - why and how to fix it ?