Newton's Law of Cooling
Tf=Ts+(Ti-Ts)e^(-kt) where Tf is temp at time t, Ts is temp of surroundings, Ti is temp of object/fluid. So we need to find k first.
200=68+(210-68)e^(-10k)
132=142e^(-10k)
132/142=e^(-10k)
ln(132/142)=-10k
k=-ln(132/142)/10
k≈0.0073 so
T(t)=68+142e^(-0.0073t) so how long until it reaches 180°?
180=68+142e^(-0.0073t)
112=142e^(-0.0073t)
112/142=e^(-0.0073t)
ln(112/142)=-0.0073t
t= -ln(112/142)/(0.0073)
t≈32.51 minutes
Answer:
the 3 one
Step-by-step explanation:
Answer:
x = 35
Step-by-step explanation:
We can use the Pythagorean theorem since this is a right triangle
a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
x^2 + 12^2 = (x+2)^2
FOIL
x^2+144=x^2+4x+4
Subtract x^2 from each side
144= 4x+4
Subtract 4 from each side
140 = 4x
Divide by 4
35 =x
18 groups of 12. 18 times 12. That equals 216. 216 can round to 200, 215, or 220.
X + (2x-1) = 41
3x - 1= 41
3x = 42
x = 14
14 and 27