Multiple drugs are often used in treating hypertension. Suppose 10% of patients taking antihypertensive agent A experience gastrointestinal (GI) side effects, whereas 20% of patients taking antihypertensive agent B experience such side effects. If the side effects of the two agents are assumed to be independent events, then what is the probability that a patient taking the two agents simultaneously will experience GI side effects from at least one of the two agents?