Here's how you can calculate it: the probability of not being allergic to shellfish. P(Not Shellfish) = 1 - P(Shellfish) P(Not Shellfish) = 1 - 0.056 P(Not Shellfish) = 0.944 find the probability of not being allergic to gluten. P(Not Gluten) = 1 - P(Gluten) P(Not Gluten) = 1 - 0.038 P(Not Gluten) = 0.962 \multiply the two probabilities together to find the combined probability. P(Not Shellfish and Not Gluten) = P(Not Shellfish) * P(Not Gluten) P(Not Shellfish and Not Gluten) = 0.944 * 0.962 Let's do the math: P(Not Shellfish and Not Gluten) = 0.908288 So, the probability that a person is not allergic to both shellfish and gluten is 0.908288, or about 90.83% when rounded to two decimal places