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Current time:0:00Total duration:5:28

Video transcript

what we have here are a few data analysis questions in a biology context from the new york regents exam but these are useful example problems if you're studying high school biology in general because they might show up in some type of an exam that your teacher gives you or you might see on the standardized test a student proposes that if volunteers warm up before squeezing a clothespin for one minute they will increase the number of times that they can squeeze it without tiring he states that this is because their muscles will be better prepared for the exercise the data from an experiment are shown in the data table below which trial from the chart above provides the best data to support his claim support your answer so pause this video and see if you could answer it so let's just make sure we understand what's going on here so there's two trials this is the first trial trial one right over here and in trial one you had two groups of ten students one of them did warm up and the other one and the other ten did not warm up and then in trial two you had two more groups and this time there were groups of twenty five once again 25 who did warm up and 25 who didn't warm up now in trial one the group that warmed up actually had a lower number of average squeezes so this goes against the hypothesis that the student had the hypothesis the student had is if they warm up beforehand then you would actually be able to do more squeezes so trial one actually goes against the students claimed trial two seems to slightly go in favor of the students claimed the group that warmed up was able to eke out a few more now we haven't done the statistical analysis to know if if how probable this is if if it was do appear early to random chance but just to answer that question one the data goes trial one goes a little bit against the students claimed trial to best supports this claim although it doesn't do it so strongly so I would say trial trial two and that is because the 25 that warmed armed up that is group 3 group 3 were able on average on average to squeeze more in a minute to squeeze more in the minute then group 4 that didn't warm up alright let's do another question here so here we're told students were asked to design a lab that investigated the relationship between exercise and heart rate heart rate was determined by recording the pulse rate in beats per minute the students hypothesized that increased exercise results in an increased heart rate the class results for the experiment are shown in the graph below and then they say which statement is best supported by this graph and were given four choices so pause this video and see if you can answer this on your own alright now let's go through a statement by statement statement one before exercising the average pulse rate was 65 for minutes after exercising the average pulse rate was 65 so let's see before exercising the average pulse rate was 65 so before actually saying this is time paired right over here and it does look like over most of that time period the medicine read it does look like that is reasonably that is roughly true it looks like the average pulse rate was 65 but now let's read the second part of the statement four minutes after exercising the average pulse rate was 65 as well four minutes after exercising what's the average pulse rate well it sure isn't 65 it looks closer to being maybe 135 not 65 so we can rule this one out after four minutes of exercising the average pulse rate was 120 let's see so this is when the exercise starts after four minutes the average pulse rate was 120 no it looks like it was like 1 135 or something like this so this is already looking fishy two minutes after exercising the average pulse rate was 120 so two minutes after exercising the average pulse rate actually seems closer to about a 90 so both of those look she I'll rule that one out while exercising the average the highest average pulse rate was 150 before exercising the average pulse rate was 65 so let's see while exercising the highest average pulse rate happens right over there and that does indeed look pretty close to 150 so this parts looking good before exercising the average pulse rate was 65 yeah we already talked about this period right over here so this is looking good I'm liking this choice but let's see choice for two minutes before exercising the average pulse rate was 80 so two minutes before exercising this is when we start exercising and each of these hash marks is a minute so two minutes before the average pulse rate was not 80 so that's false two minutes after two minutes of exercise the average pulse rate was 140 after two minutes the average pulse rate was also not 140 so both of those statements are not correct so I like statement three that's the one that seems to be backed up by the data here
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