excel：如何将概率与“或”组合？

Question

I have a range B2:F2 which contains probabilities of different events, eg,

0.9  0.7  0.1  0  0.3

The probability of the "and" event is he product of the probabilities (assuming independence) and can be computed using product(b2:f2) .

The probability of the "or" event is 1-product(1-(b2:f2)) but that results in the #VALUE! .

So, do I really need to resort to typing 1-(1-b2)*(1-c2)... explicitly?

Answer 1

You're almost there - type the formula you have already ( =1-product(1-B2:F2) ) then press Ctrl+Shift+Enter (instead of Enter) to make it an array formula.

In this case the result itself is not an array, but the application of the array formula modifies the behaviour of the subtraction operator for 1-B2:F2 to apply the operation to each element of the input range.

Answer 2

Your Product function works but it's an "array formula" that needs to be confirmed with CTRL + SHIFT + ENTER so that curly braces like { and } appear around the formula in the formula bar

=1-PRODUCT(1-B2:F2)

....or alternatively you can add an INDEX function which means it can be normally entered, ie

=1-PRODUCT(INDEX(1-B2:F2,0))