Answer:
65
Step-by-step explanation:
You can use f(15) = 40 to solve for C, then find f(0), the initial temperature.
40 = f(15)
40 = Ce^(-0.045·15) +14 = .50916C +14
26 = .50916C
26/.50916 = C ≈ 51.065
Then f(0) is ...
f(0) = 51.065·e^0 +14 = 65.065 ≈ 65
The initial temperature of the water was 65 degrees Fahrenheit.
Answer:
t = 137.9 years
Step-by-step explanation:
Hi, to answer this question we have to apply an exponential growth function:
A = P (1 + r) t
Where:
p = original population
r = growing rate (decimal form)
t= years
A = population after t years
Replacing with the values given:
A = 6,250 (1 + 3.75/100)^t
A = 6,250 (1 + 0.0375)^t
A = 6,250 (1.0375)^t
1915-1890 = 25 years passed (t)
A = 6,250 (1.0375)^25
A = 15,689
1940-1890 = 50 years passed (t)
A = 6,250 (1.0375)^50
A = 39,381
- When will the population reach 1,000,000?. We have to subtitute A=1000000 and solve for t.
1,000,000= 6,250 (1.0375)^t
1,000,000/ 6,250 =(1.0375)^t
160 = 1.0375^t
log 160 = log 1.0375^t
log 160 = (t ) log 1.0375
log160 / log 1.0375= t
t = 137.9 years
Before we could add these numbers, 3/8 and 7/10 need a common denominator. Both 8 and 10 go into 40.
8 goes into 40 five times
3/8= (3*5)/40 = 15/40
10 goes into 40 four times
7/10= (7*4)/40= 28/40
ANSWER: A) 15/40 and 28/40
Hope this helps! :)
The answer is the first choice - see picture for solution: