Asample of 12 measurements has a mean of 8.5 and a sample of 20 measurements has a mean of 7.5. find the mean of all 32 measurements

The mean of the first 12 measurements is 8.5 units, which is the average.
Then the second 20 measurements have an average of 7.5 units.
To find the mean (or the average) you add all measurements and then divide the sum by the number of measurements.
So you will do 12 times 8.5 plus 20 times 7.5 and divide it all by 32.
You get 102+150 which is 252 and divide it by 32, which is 7.875. 
The mean of all 32 measurements is 7.875 units.
I hope this is helpful, but if you have any other questions, feel free to comment below.

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The answer is 270 cars.you can do this by making a proportional relationship. for instance, 200 is the whole we are using, so on a “number line” 200 would be over 100%. now, since he sells 35% more, add 35% to 100% to get 135% on the other side of the “number line” on the bottom half, leaving the top half empty.cross multiply 200 by 135 then divide by 100 to get your answer. i hope this , if it did, , if you don’t mind, giving me brainiest! 200/100% } 200 • 135 /100 ? /135%