The answer is D.
9/12 = 3/4
16/24 = 2/3
2/3 is not equivalent to 3/4
Since

, we know that

follows a Poisson distribution with parameter

.
Now assuming

denote the mean and standard deviation of

, respectively, then we know right away that

and

.
So,
X+y+z=t
simple..
there are no other numbers that we have to follow like (1/2x or 3/4y) so it is just all together=t. the x, y, z will equal t because t is the total number of students taking three languages. And that number should be equivalent to x,y,z combined.
otherwise?? i d k<span />
Answer:
Ok so here are the simple rules of doing it (very easy) cause I’m not doing it all so . when multiplying a power with The same base keep the base but add the exponents. Dividing, keep the base (if their the same if not then its already simplified same with multiplication) but SUBTRACT the exponents. Also keep the parenthesis if it’s a negative number base.
I’ll do a few.
11) a^10. 11b) 5^4
12) (-2)^2.
13) 10^2. 13b) s^6
14) -4s^5(t^6) <- [Im not sure of this one)
15) x^3(y^3)