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Current time:0:00Total duration:2:21

Video transcript

according to the pictograph below how many survey respondents have type O+ blood how many have o negative blood so a pictograph is really just a way of representing data with pictures that are somehow related to the data so in this case they give us little pictures of I'm assuming blood drops right over here and then they tell us that each blood drop each blood drop in this pictograph represents eight people so you can kind of view that as a scale of these graphs each of these say eight people so for example if you say how many people have a positive would be one two three four five six seven blood drops but each of those blood drops represent eight people so it would be fifty six people have type a positive but let's answer the actual question that they're asking us how many survey respondents have type O+ Oh positive so this is oh and then we care about o+ so we have one blood drop to three let me do this in a new different color we have one two three four five six seven eight so we have eight drops I'll put it those in quotes because pictures of drops and then the scale is the scale is eight people eight people let me write it this way times eight people per drop eight people per drop and so eight times eight and actually even the drops you can view them as cancelling out if you view them as units so drops drops eight times eight is equal to 64 64 people so they could have written literally the number 64 right over here sixty-four people have type O+ blood now let's think about the o-negative case Oh negative blood well this is oh and then within the blood group O this is o-negative and we have one drops two drops so we have two drops two drops times eight people per drop eight people per drop and so two times eight each of these represent 8 so 8 and then 16 or 2 times 8 is equal to 16 16 people so sixteen of the survey respondents 16 have type-o negative 64 have type O+