I think the correct answer from the choices listed above is option B. Quadrilateral ABCD must be a rectangle because it is characterized by having <span>opposite sides that are parallel and side AB congruent to side DC which are characteristics of a rectangle.</span>
So if they all add 4 hours to their time then they have:
Jeff 9
Mark 14
Karen 9
Costas 13
Brett 11
Nikki 9
Jack 11
so now to find the mean you add all the numbers together to get 76 and then you divide it by the number of people (7 people) so 76 divided by 7 equals 10.8571429 and that's the mean.
Now to find the median you put all the numbers in order from least to greatest: 9;9;9;11;11;13;14 and you take the number in the middle but since both 11 and 11 are in the middle you take the mean of them and the mean of them is 11 so the median of the numbers is 11
now to find the range you take the largest number (14) and you subtract the smallest number (9) so 14 - 9 is 5 so 5 is the range
and last the mode is the number that is repeated most out of all the numbers so the mode would be 9
30/78 simplified is 15/39
Answer:
130°
Step-by-step explanation:
90° ± 90° = 180°
180° - 50° = 130°
130°