Answer:
Chi-square value = 2
Step-by-step explanation:
Given data:
Frequency: Tall Short
30 20
Null hypothesis ( as it is already given so there is no difference between observed and expected values)
Ratio: 1:1 (50% expected frequency of each tall and short pea-plant)
Solution:
Phenotype Observed Expected O-E (O-E)² (O-E)
O E
Short 20 25 -5 25 1
TALL 30 25 5 25 1
TOTAL 2
So, from all these calculations using expected and observed values we get chi-square value equal to 2.