Question 424563
Show all work. Mary purchased a package of 20 different plants, but she only needed 16 plants for planting. In how many ways can she select the 20 plants from the package to be planted?
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Note: # of ways of selecting 16 is the 
same as # of ways of not selecting 4.
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20C16 = 20C4 = (20*19*18*17)/(1*2*3*4) = 4845
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Cheers,
Stan H.