Answer:
3200 people
Step-by-step explanation:
p = The frequency of the dominant gene
q = The frequency of the recessive gene
p+q = 1
⇒p = 1-q
⇒p = 1-0.2
⇒p = 0.8
Hardy-Weinberg formula
p² + 2pq + q² = 1
Now for heterozygous trait
2pq = 2×0.8×0.2 = 0.32
Multiplying with the population
0.32×10000 = 3200
∴ 3200 people would be expected to be heterozygous for this trait.