Answer:
Interval notation: 
Step-by-step explanation:
<u>First inequality:</u>
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Therefore, this inequality restricts:
<u>Second inequality:</u>
Therefore, this inequality restricts:
Therefore, with both of these restrictions together, we have:
.
Step-by-step explanation:
ah, here you go.
come on, now. you know this now ...
again, mutually exclusive attributes in the table (no overlap here) allow us to add the numbers for a total :
4+2+12+10 = 28 students in total.
how many of those 28 fulfill our desired criteria (has a brother) ?
well, it is the sum of the column "has a brother", as it does not matter, if there is also a sister or not.
so, it is 4 + 12 = 16
therefore, the probability to pick a student randomly, who has a brother is
16/28 = 4/7 = 0.571428571...
Check the picture below.
since we know that x = 3/7, we can then plug that on either of the twin legs, since it's an isosceles, and get the length of each leg, so say let's plug it in 5x + 16
![5x + 16\implies 5\left( \cfrac{3}{7} \right)+16\implies \cfrac{38}{7}+16\implies \cfrac{38+112}{7}\implies \cfrac{150}{7}\\\\[-0.35em]\rule{34em}{0.25pt}\\\\\stackrel{\textit{both legs}}{\cfrac{150}{7}+\cfrac{150}{7}}+\stackrel{\textit{base}}{6}\implies \cfrac{150+150+42}{7}\implies \cfrac{342}{7}\implies 48\frac{6}{7}\impliedby \textit{perimeter}](https://tex.z-dn.net/?f=5x%20%2B%2016%5Cimplies%205%5Cleft%28%20%5Ccfrac%7B3%7D%7B7%7D%20%5Cright%29%2B16%5Cimplies%20%5Ccfrac%7B38%7D%7B7%7D%2B16%5Cimplies%20%5Ccfrac%7B38%2B112%7D%7B7%7D%5Cimplies%20%5Ccfrac%7B150%7D%7B7%7D%5C%5C%5C%5C%5B-0.35em%5D%5Crule%7B34em%7D%7B0.25pt%7D%5C%5C%5C%5C%5Cstackrel%7B%5Ctextit%7Bboth%20legs%7D%7D%7B%5Ccfrac%7B150%7D%7B7%7D%2B%5Ccfrac%7B150%7D%7B7%7D%7D%2B%5Cstackrel%7B%5Ctextit%7Bbase%7D%7D%7B6%7D%5Cimplies%20%5Ccfrac%7B150%2B150%2B42%7D%7B7%7D%5Cimplies%20%5Ccfrac%7B342%7D%7B7%7D%5Cimplies%2048%5Cfrac%7B6%7D%7B7%7D%5Cimpliedby%20%5Ctextit%7Bperimeter%7D)
