3. 9a+9b
4. 3n+21
5. 30+2q
6. ab+8a
Answer:
And we can find the probability with this difference:
And using the normal standard table or excel we got:
And the best answer would be:
0.3811
Step-by-step explanation:
Let X the random variable that represent the ratings of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
Using the z score we got:
And we can find the probability with this difference:
And using the normal standard table or excel we got:
And the best answer would be:
0.3811
X=9.8/-4.9
X=-2
The answer is -2