The ratio of males to females is 1.4 : 1, so the fraction of the total that is made up of males is 1.4/(1.4 + 1) = 1.4/2.4 = 7/12.
There were (7/12)*475 ≈ 277 males at the party.
There were 475 - 277 = 198 females at the party.
(8.5*12.4)^(1/2)=10.266
In general the geometric mean is (ab)^(1/2), (abc)^(1/3), (abcd)^(1/4), etc
The nth root of the product of n elements.
We define the probability of a particular event occurring as:

What are the total number of possible outcomes for the rolling of two dice? The rolls - though performed at the same time - are <em>independent</em>, which means one roll has no effect on the other. There are six possible outcomes for the first die, and for <em>each </em>of those, there are six possible outcomes for the second, for a total of 6 x 6 = 36 possible rolls.
Now that we've found the number of possible outcomes, we need to find the number of <em>desired</em> outcomes. What are our desired outcomes in this problem? They are asking for all outcomes where there is <em>at least one 5 rolled</em>. It turns out, there are only 3:
(1) D1 - 5, D2 - Anything else, (2), D1 - Anything else, D2 - 5, and (3) D1 - 5, D2 - 5
So, we have

probability of rolling at least one 5.
Walter I believe is the correct answer