Since multiplying by 0.5 is the same as dividing by 2, the problem is described by the sentence
"Half the sum of a number and 40 equals 200"
It at the top all you had to do was divided bot ways you will get that answers
No she is not correct
80 x.70 is 56 as you wrote, and it says 70% wait LESS THAN 30 minutes
On the left of the graph, time, you go to 30 minutes and the patients are much less (21) than 56 patients
ANSWER: No
This is the concept of differential equations, given that
dp/dt=rp
then:
dp/p=rdt
thus:
ln p=rt+C
p=e^(rt+C)
P=Ke^(rt)
when t=210 days=7 months, p=2k
2k=k×e^(7r)
2=e^(7r)
ln2=7r
r=ln(2)/7
r=0.0990