Due to the cross between TTRr and ttrr the resultant progenies showed how many percent of plants would be tall, red-flowered?

Concept: The gene for  tall growth of plants is represented by "T" and dwarfism is represented by "t". The red blood gene is represented by the "R" and the white blood gene is represented by the gene "r". In that case, the parental genotype would be heterozygous large red-blooded TTRr and homozygous dwarf white-blooded ttrr. 
Parent Phenotype – Crimson x Dwarf White 
Parental genotype – TTRr × ttrr 
Gamete – TR, Tr, tr, tr

F1 generation phenotype-big red-2, big white-2 
F1-generation genotypes-TtRr and Ttrr 
Therefore, the proportion of large red flowers in the mating of TTRr and ttrr is 50%. 
Therefore, the correct answer is 50%.