Answer:
The number of parents who volunteered to bring refreshments is 16.
Step-by-step explanation:
The information provided is:
N = 84
n (S) = 35
n (S ∩ R) = 11
n (R) = 1.5 × n (S' ∪ R')
Compute the value of n (S ∪ R) as follows:
![n(S\cup R)=n(S)+n(R)-n (S\cap R)\\\\n(S\cup R)=n(S)+[1.5(N-n(S\cup R)]-n (S\cap R)\\\\n(S\cup R)=n(S)+1.5N-1.5n(S\cup R)-n (S\cap R)\\\\2.5n(S\cup R)=n(S)+1.5N-n (S\cap R)\\\\2.5n(S\cup R)=35+(1.5\times84)-11\\\\2.5n(S\cup R)=150\\\\n(S\cup R)=\frac{150}{2.5}\\\\n(S\cup R)=60](https://tex.z-dn.net/?f=n%28S%5Ccup%20R%29%3Dn%28S%29%2Bn%28R%29-n%20%28S%5Ccap%20R%29%5C%5C%5C%5Cn%28S%5Ccup%20R%29%3Dn%28S%29%2B%5B1.5%28N-n%28S%5Ccup%20R%29%5D-n%20%28S%5Ccap%20R%29%5C%5C%5C%5Cn%28S%5Ccup%20R%29%3Dn%28S%29%2B1.5N-1.5n%28S%5Ccup%20R%29-n%20%28S%5Ccap%20R%29%5C%5C%5C%5C2.5n%28S%5Ccup%20R%29%3Dn%28S%29%2B1.5N-n%20%28S%5Ccap%20R%29%5C%5C%5C%5C2.5n%28S%5Ccup%20R%29%3D35%2B%281.5%5Ctimes84%29-11%5C%5C%5C%5C2.5n%28S%5Ccup%20R%29%3D150%5C%5C%5C%5Cn%28S%5Ccup%20R%29%3D%5Cfrac%7B150%7D%7B2.5%7D%5C%5C%5C%5Cn%28S%5Ccup%20R%29%3D60)
Now compute the value of n (R) as follows:
![n (R) = 1.5 \times n (S' \cup R') \\\\n (R) = 1.5 \times [N-n (S \cup R)]\\\\n (R) = 1.5 \times [84-60]\\\\n(R)=16](https://tex.z-dn.net/?f=n%20%28R%29%20%3D%201.5%20%5Ctimes%20%20n%20%28S%27%20%5Ccup%20R%27%29%20%5C%5C%5C%5Cn%20%28R%29%20%3D%201.5%20%5Ctimes%20%20%5BN-n%20%28S%20%5Ccup%20R%29%5D%5C%5C%5C%5Cn%20%28R%29%20%3D%201.5%20%5Ctimes%20%20%5B84-60%5D%5C%5C%5C%5Cn%28R%29%3D16)
Thus, the number of parents who volunteered to bring refreshments is 16.
Answer: x< -8
Step-by-step explanation:
Answer:
In 2009
Step-by-step explanation:
If the wren population is going down by 40% each year, that means the following year's population is just 60% of what was in the previous year. This means that what we have to do is multiply the previous year's number by 0.6 to get the current year's population. If we take the data from 2004 as 100%, we have the following numbers:
2004 = 100%
2005 = 60 % (100 * .6)
2006 = 36 % (60 * .6)
2007 = 21.6 % (36 * .6)
2008 = 12.96 % (21.6 * .6)
2009 = 7.776% (12.96 * .6)
This means that 2009 will show that the wren population is less than 10% (7.776%) than what it was in the year 2004.
I hope this helps! :D
Answer:
x = 9/8
Step-by-step explanation:
You would use proportions in this case.
9/9+x = 1/x
9x = 9 + x
8x = 9
x = 9/8
Answer:
A
Step-by-step explanation:
