In pea plants, the allele for tall stem length (TTT) is dominant to the allele for short stem length (ttt). Two heterozygous tall pea plants (TtTtTt) are crossed. The table below shows the number of tall and short offspring produced from this cross:
| Phenotype | Number of offspring |
|---|---|
| Tall | 735 |
| Short | 245 |
Calculate the number of these offspring that is most likely to be heterozygous.