Testing for a disease can be made more efficient by combining samples. If the samples from people are combined and the mixture tests​ negative, then samples are negative. On the other​ hand, one positive sample will always test​ positive, no matter how many negative samples it is mixed with. Assuming the probability of a single sample testing positive is ​, find the probability of a positive result for samples combined into one mixture. Is the probability low enough so that further testing of the individual samples is rarely​ necessary?