With nothing to do any testing with, give this a try:

WITH BaseData(

Class,

Date_Entered,

PMmiles,

RO,

RoDate,

Time_In,

Ranking

)AS(

SELECT --RO,Time_In, Ranking = DENSE_RANK() OVER (PARTITION BY RO,Time_In ORDER BY NEWID() ASC)

Class,

Date_Entered,

PMmiles,

RO,

RoDate,

Time_In,

Ranking = row_number() over (partition by RO, RoDate, Time_In order by (select null))

FROM

DTAGatHERTZ_RO

)

INSERT INTO ROs

SELECT

Class,

Date_Entered,

PMmiles,

RO,

RoDate,

DATEADD(mi,Ranking - 1, Time_In

from

BaseData

where

RO = '4187';