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.
I think the answer is B but I’m not sure, sorry if i got it wrong,
have a good day and have a good Christmas
The third angle is 180-55-65 = 60°.
Exterior angles are 180-55 = 125°, 135°, 120°
1 30 30
-- x ---- = ---- ---> 30/5 = 6
5 1 5
30 is a full number but it can turn into a fraction. The whole number (30) will be the numerator (the top number) and 1 is basically "the quantitative number" aka the denominator (the bottom number).
The final result of this problem is 30 over 5. Which you can divide. Always divide the numerator to the denominator to get your answer (for this kind of problem).
It’s rational, for a number to be rational you have to be able to write it as a fraction and you can write 0.515115111511115111115... as a fraction.
