How would u calculate the below?

A firm needs to find 100 people who regularly purchase orange juice to complete a survey on a new frozen juice. They sampled 500 people %26amp; 75 orange juice buyers have been found. Based upon this info - how many additional people in random sample do they need to interview to reach an expected total of 100 people who regularly purchased orange juice?





How would u calculate this?

How would u calculate the below?
75/500 = 100/x


75*x = 100*500


x = 50000/75


x = 667





They've already interviewed 500, so if the ratio stays the same, they need to interview an additional 167.
Reply:set the follow (75/500) = (100/x) solve for x
Reply:500 Surveyed - 75 orange buyers found


X Surveyed - 100 orange buyers found





500 * 100 = 50000





50000/75 = 666.67





Additional required = 500-666.67 = 166.67 (round off to 167)
Reply:100/75(500)=2000/3=670 approximately
Reply:so with the first 500 people they found 75% of the people the need (75 out of 100). So they need 25% more. 25% of 500 is 125
Reply:Well is 75 buyers were found out of 500 people, you could write this as a fraction





75/500





If you assune that you will get a proportionate response from other people surveyed then you can write a proportion





75/500 = 100/x





Where 100 is the desired number and x is unknown.





Now all you have to is solve for x.


Multiply both sides by x gives





75x/500=100x/x and simplify gives





75x/500=100





Multiply both sides by 500 gives





500 * (75x/500) = 500 * 100





Divide both sides by 75 gives





500/75 * (75x/500) = (500 * 100) / 75 and simplify





x = 666 2/3 (you'd need to call that 667th person)

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