Newton's Law of Cooling states that the change
of the temperature of an object is proportional to the difference between its
own temperature and the ambient temperature over time.
Therefore when expressed mathematically, this is equivalent
to:
dT = - k (T – Ts) dt
dT / (T – Ts) = - k dt
Integrating:
ln [(T2– Ts) / (T1– Ts)] = - k (t2 – t1)
Before we plug in the values, let us first convert the
temperatures into absolute values R (rankine) by adding 460.
R = ˚F + 460
T1 = 200 + 460 = 660 R
Ts = 70 + 460 = 530 R
ln [(T2– 530) / (660 – 530)] = - 0.6 (2 - 0)
T2 = 569.16 R
T2 = 109 ºF
Answer: After 2 hours, it will be 109 ºF
60%_____18
90%______x
x = 90×18/60 = 27
There are 5 groups of 3 in the number 15, so 15/3=5
Answer:
The unit rate is 
Step-by-step explanation:
Given : Kenny reads
page in
min.
To find : What is Kenny's unit rate?
Solution :
Kenny reads
page in
minute
This can be written as,

Divide both side by 


The unit rate is 
Answer:
old per: 1280
new per:2560
Step-by-step explanation:
first perimeter u get it by adding all the sides and since its a square then all the sides are equal so u can just do
320*4 which is equal to 1280
and by doubling the sides u can just double it in the old equation meaning
(320*2)*4
which is equal to 2560