Using the Newton's law of cooling, the time it takes to cool to 100°F is 116 mins.
<h3>Newton's law of cooling</h3>
According to the Newton's law of cooling, the when an object is exposed to the surrounding it looses heat rapidly untill it is at a thermal equilibrium with the suurroundings.
Now;
T(t) = T(s) + (To - Ts)e^-kt
T(t) = temperature at time T
To = initial temperature
Ts = temperature of the surrounding
k = colling constant
t = time taken
200 = 68 + (230 - 68)e^-15k
200 = 68 + 162e^-15k
200 - 68/162 = e^-15k
ln(0.815) = -15k
k = ln(0.815)/-15
k = 0.014 min-1
Now;
100 = 68 + (230 - 68)e^-( 0.014t)
100 -68/162 = e^-( 0.014t)
0.198 =e^-( 0.014t)
ln(0.198) = -( 0.014t)
t = ln(0.198)/-0.014
t = 116 mins
Learn more about newtons law of cooling: brainly.com/question/14643865:
Answer:
1). Mean: 14.2
Median: 13.5
Step-by-step explanation:
To calculate the mean, sum all values and divide by the number of values:
(13+16+14+17+13+12) / 6 ≈ 14.2
To calculate the median, order the values from small to large and take the middle value. If there is no middle. average the two values in the middle:
12,13,<u>13,14</u>,16,17
The median is (13+14)/2 = 13.5.
Using this explanation you should be able to find the rest.
Yes, they are! If you divide 63/3 you get 21, and if you divide 147/7 you get 21!:)
First set both equations equal to y
y = -1/2x + 3
y = 3x - 4
Then set these two equal because they both equal y
-1/2x + 3 = 3x + 4
Combine like terms and solve
7 = 3.5x
x = 2
y also = 2 when you plug it back in
Therefore, (2,2)
