Question 421251
I have a probability distribution of customers visiting a store as follows: 
18% of customers come 2x a week
25% of customers come 3x a week
33% of customers come 4x a week
13% of customers come 5x a week
8% OF customers come 6x a week
3% of customers come 7x a week 
How many unique customers do I need to have a total of 400 customers every week? Assuming that every visitor is a customer and will purchase.
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Let "x" be the number of unique customers:
Solve:
2*0.18x + 3*0.25x + 4*0.33x + 5*0.13x + 6*0.08x + 7*0.03x = 400
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0.36x + 0.75x + 1.32x + 0.65x + 0.48x + 2.1x = 400
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5.66x = 400
x = 70.67 unique customers
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Cheers,
Stan H.
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