 In this video we provide the solution to question number 11 for practice exam number 4 for Math 1030, in which case we have the following situation. The smell and taste treatment and research foundation conducted a study to investigate whether smell can affect learning. Okay, that'd be kind of fun to know. Subjects completed mazes multiple times while wearing masks. They completed the pencil and paper mazes three times wearing floral scented masks and three times with unscented masks. Okay, participants were assigned at random to wear the floral mask during the first three trials or during the last three trials. For each trial, researchers recorded the time it took to complete the maze and the subject's impression of the mask scent, positive, negative, or neutral. What kind of blinded study is this? Well, as we look at these situations, a single blind situation would be that the participants don't know if they're in the control group or the treatment group. A double blind study would be a situation where both the participant and the conductors of the research don't know whether the participants are in the control group or the treatment group here. So notice here that the control group would be the unscented mask and the treatment group would be the floral scented mask. But as the participants are going to be wearing both the floral and the unscented mask, perhaps at the beginning or the end, it depends. That's randomized to make sure it doesn't matter which one comes first. But all participants are having the scented mask and the unscented mask. So there is no blindness in this study. Everyone knows what the treatment is and what's not the treatment. So the answer would be here to see. This is neither a single blind or double blinded study.