Finding nearest value from table with respect to selected value in slicer

PowerBi_Xandar , create measures like

Qty M =
var _max = mInx(filter(Table, [Qty]>= selectedvalue('Quantity Table'[value])), Table[Qty])
var _min = Maxx(filter(Table, [Qty]<= selectedvalue('Quantity Table'[value])), Table[Qty])
return
calculate(Sum(Table[Qty]), filter(Table, Table[Qty] =if(_max -[Qty]> [Qty] -_min , _min, _max)))

Price M =
var _max = mInx(filter(Table, [Qty]>= selectedvalue('Quantity Table'[value])), Table[Qty])
var _min = Maxx(filter(Table, [Qty]<= selectedvalue('Quantity Table'[value])), Table[Qty])
return
calculate(Sum(Table[Price]), filter(Table, Table[Qty] =if(_max -[Qty]> [Qty] -_min , _min, _max)))

or use one of them a visual level filter

Hi PowerBi_Xandar 

The approach amitchandak  offers is fantastic,  In addition to referring to the solutions amitchandak provides, you can also consider the following methods. 

You can refer to the following measure

Price = VAR A=SELECTEDVALUE(Quantity[Value])
var b=ADDCOLUMNS(ALLSELECTED('Rate'),"Divide",IF(a>[Qty],DIVIDE(a,[Qty]),DIVIDE([Qty],a)))
var c=SUMMARIZE(b,[Seq ],'Rate'[Qty],'Rate'[Price],[Divide],"Min",MINX(b,[Divide]))
return MINX(FILTER(c,[Min]=[Divide]),[Price])

QTY = VAR A=SELECTEDVALUE(Quantity[Value])
var b=ADDCOLUMNS(ALLSELECTED('Rate'),"Divide",IF(a>[Qty],DIVIDE(a,[Qty]),DIVIDE([Qty],a)))
var c=SUMMARIZE(b,[Seq ],'Rate'[Qty],'Rate'[Price],[Divide],"Min",MINX(b,[Divide]))
return MINX(FILTER(c,[Min]=[Divide]),[Qty])

Output

Best Regards!

Yolo Zhu

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