`Manipulate[
 Column[{tog[n],
   Button["reset samples", {n = 1000,
     samphorm =
      Transpose[{RandomReal[{0, 3}, {10000}],
        RandomReal[{0, 2}, {10000}]}];
     sampcmc = 3 RandomReal[{0, 1}, {10000}];
     sampva = 3 RandomReal[{0, 1}, {10000}]}]}], {{n, 1000,
   "sample size"}, 200, 10000, 50, Appearance -> "Labeled"},
 Initialization :> {
   SeedRandom[12345];
   horm[n_] :=
    a = ListPlot[
      4. 6 Accumulate[
         If[# == True, 1,
            0] & /@ (#[[2]] <= 2 Sqrt[1 - (#[[1]])^2/9] & /@
            Take[samphorm, n])]/Range[n],
      PlotStyle -> {GrayLevel[0],
        PointSize[
         Which[n < 100, 0.007, n < 1000, 0.004, True, 0.004]]},
      PlotLabel -> Style[
        Grid[{
          {"Metoda hit-or-miss: czarne kropki"}, {"Metoda surowa \
Monte Carlo: czerwone kropki"}, {"Metoda przeciwstawnych zmiennych: \
niebieskie kropki"}}, Alignment -> Center, Spacings -> 0.3], "Label",
        9], AxesOrigin -> {0, 8.5}, ImageSize -> {800, 600},
      Epilog ->
       Tooltip[{Opacity[0.5], Orange, Thickness[0.005],
         Line[{{0, 18.85}, {n, 18.85}}]}, "True area = 18.85"],
      PlotRange -> {{0, n}, {16.2, 20.6}}];
   cmc[n_] :=
    b = ListPlot[
      4 6 Accumulate[( Sqrt[1 - #^2/9] & /@ Take[sampcmc, n])]/
        Range[n],
      PlotStyle -> {PointSize[
         Which[n < 100, 0.007, n < 1000, 0.004, True, 0.004]],
        Hue[1]}];
   mcva[n_] := (r1 =
      4 6 Accumulate[( Sqrt[1 - #^2/9] & /@ Take[sampva, n])]/
        Range[n];
     r2 = 4 6 Accumulate[(
          Sqrt[1 - (3 - #)^2/9] & /@ Take[sampva, n])]/Range[n];
     c = ListPlot[(r1 + r2)/2,
       PlotStyle -> {Hue[0.7], PointSize[0.004]}]);
   tog[n_] := (horm[n]; cmc[n]; mcva[n];
     Show[a, b, c, ImageSize -> {800, 600}, ImagePadding -> 20]);
   samphorm =
    Transpose[{RandomReal[{0, 3}, {10000}],
      RandomReal[{0, 2}, {10000}]}];
   sampcmc = 3 RandomReal[{0, 1}, {10000}];
   sampva = 3 RandomReal[{0, 1}, {10000}];
   }]`