In a cross between tall and dwarf in F2 generation how many are hybrid tall ?

In a cross between two F1 hybrids (both Tt), the genotype and the phenotype of the progeny can be easily seen by observing the following Punnet Square. 
Gametes  T   t
t Tt tt

As you can see from the Punnet Square, there are 75 % of the progeny showing the dominant character of tallness (individuals with genotypes TT and Tt) and 25% of the progeny showing the recessive character of dwarfness (individuals with the genotype tt). It is clear by studying the genotypes that all individuals showing dominant character are not similar. Out of 75%, 25% of the progeny are homozygous (TT) for the dominant character of tallness, whereas 50% are heterozygous (Tt). Thus, 50% of the progeny are hybrids.
This crossing of hybrids of the F1 generation gave rise to the following Monohybrid ratio:
Phenotypic ratio: 3:1
Genotypic ratio: 1:2:1
An important point to note here is that the Punnet Square does not show the actual number of the individuals rather it depicts the percentages of the genetic make-up of the progeny. 

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TT X tt
T t
Tt X Tt
TT Tt Tt tt
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