D
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It is possible for two different inputs to give you the same output. For example, -2 and 2 produce the same result: 5.
it is not possible to derive two different outputs from the same input. This is because a) 
is a function making it impossible to have two outputs and b) for each value, if you square it, you only get one value, then adding one, making it one certain value.
Let x be the original price. The discount on this item is 64% of x, that means:
discount = x(0.64) = $30, x = 30/0.64 = original price x = $46.875:
Write an equation:
NET PRICE = Original price - discount (on the original price)
NET PRICE = x - 0.64.x or NET PRICE = x(1-0.64)
NET PRICE =0.36.x
Looking at Pascal's Triangle, specifically at the row that starts with 1, 10, etc we see the value 210 in the 4th slot (start the count at 0) since 10-6 = 4
Or you can use the combination formula nCr to get the same result
nCr = (n!)/(r!*(n-r)!)
10C4 = (10!)/(4!(10-4)!)
<span>10C4 = (10!)/(4!*6!)
</span><span>10C4 = (10*9*8*7*6!)/(4!*6!)
</span><span>10C4 = (10*9*8*7)/(4!)
</span><span>10C4 = (10*9*8*7)/(4*3*2*1)
</span>10C4 = 210
Either way, the final answer is Choice C) 210
