Step-by-step explanation:
Total number of tables in the cafeteria = 20
65% of the tables = 
= 13
Each table has 6 chairs.
So, total number of chairs that 65% of the tables have = 13 × 6 = 78.
35% of the tables = 
= 7
Each table has 4 chairs.
So, total number of chairs that the remaining 35% of the tables have = 7 × 4 = 28.
Hence, total number of chairs in the hospital cafeteria = 78 + 28 = 106.
Answer:
a) This is an Observational Study because in this kind of study investigators observe subjects and measure variables of interest without assigning treatments to the subjects. Here, the Gilham et al. (2005) studied two different groups where no treatment or intervention was done. These groups were independent of each other.
b) proportions of children with significant social activity in children with acute lymphoblastic leukemia = 1020/1272 = 0.80
proportions of children with significant social activity in children without acute lymphoblastic leukemia = 5343/6238 = 0.86
c) Odds ratio can be calculated using the following formula:
OR= \frac{a/b}{c/d}
where: a - Number in exposed group with positive outcome(here this means number of children with significant social activity associated with acute lymphoblastic leukemia)
b- Number of children without social activity having with acute lymphoblastic leukemia
c- Number of children with social activity having without acute lymphoblastic leukemia
d- Number of children without social activity having without acute lymphoblastic leukemia
OR= \frac{1020/252}{5343/895}
OR= 0.6780
d) The 95% confidence interval of this Odds Ratio is 0.5807 to 0.7917.
e) Since the odds ratio lies in this confidence interval indicate that the amount of social activity is associated with acute lymphoblastic leukemia. The children with more social activity have a higher occurrence of acute lymphoblastic leukemia.
PQ = 9
QR = 28
Note, there is a Q in each line
Combine the two lines: PQ + QR = PR
plug in the numbers to corresponding variables
9 + 28 = PR
PR = 37
hope this helps
You should get 53 degrees.
