Let's solve the problem step by step: ### **Step 1: Calculate the Expected Number of Double Crossovers** First, we need to calculate the expected frequency of double crossovers between the two intervals (D–E and E–F): - Recombination frequency between D and E = 15 cM = 0.15 - Recombination frequency between E and F = 25 cM = 0.25 **Expected frequency of double crossovers:** \[ \text{Expected frequency} = (\text{frequency D–E}) \times (\text{frequency E–F}) = 0.15 \times 0.25 = 0.0375 \] **Expected number of double crossovers:** \[ \text{Expected number} = \text{Expected frequency} \times \text{Total progeny} = 0.0375 \times 726 = 27.225 \] --- ### **Step 2: Coefficient of Coincidence (c)** \[ \text{Coefficient of Coincidence (c)} = \frac{\text{Observed Double Crossovers}}{\text{Expected Double Crossovers}} \] \[ c = \frac{11}{27.225} \approx 0.404 \] --- ### **Step 3: Coefficient of Interference (I)** \[ I = 1 - \text{Coefficient of Coincidence} \] \[ I = 1 - 0.404 = 0.596 \] --- ### **Final Answer:** **The coefficient of interference (I) is approximately \(\boxed{0.60}\) (rounded to two decimal places).** If you need further explanation, let me know!