Total number of meiotic divisions occur in solitary  cyme of Hibiscus having 20 stamens with 10PMCs in each micro – sporangium and 10 ovules in  each carpel is

         Anther is monothecus in Hibiscus

          Number of sporangia in monothecus anther -2 ( bisporangiate )

          10 PMC are present in each microsporangium

           Each PMC undergoes one meiosis and produces four pollen grains

          One sporangium - 10 PMC – 10 meiosis

          Two sporangium -20 PMC – 20 meiosis

          Number of stamens 20 X 20= 400

          Ovary is penta carpellary in Hibiscus

          Number of ovules present in each carpel -10

         One of the nucellus present in micropolar end differentiates into megaspore mother cell in     ovule , megaspore mother cell undergoes meiosis and produces four megaspores

        Number of meiosis occurs in each ovule -one( 10 ovules – 10 meiosis )

        Number of carpels 5 X10= 50

        400+50=450