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
Given:
Amount = Rs. 9,144
Time = 3 years.
Rate of simple interest = 9%
To find:
The principal value.
Solution:
The formula for simple interest is:

Where, P is principal, r is the simple rate of interest, and t is the number of years.
Putting
in the above formula, we get



We know that,



Divide both sides by 1.27, we get


Therefore, the principal value is Rs. 7200.
A. For y= 2x-1, the slope is 2 and the y intercept is -1. Therefore, we should first plot (0,-1). From there, for each increment of x, increase y by 2. For y= 4x-5, the slope is 4 and the y ntercelt is -5. Therefore we should plot (0,-5) and plot an increase of 4 on the y axis per increase of 1 on the x axis. The solution is where the lines cross.
B. (2,3)
Answer:
B.
Step-by-step explanation:
Answer:
an = 1/2 (4)^ (n-1)
a6 = 512
Step-by-step explanation:
The formula for a geometric sequence is
an = a1 (r)^(n-1)
where an is the term of the sequence
a1 is the initial term of the sequence
r is the ratio
and n is the term number
We know a1 = 1/2 and r =4
I will assume that x=6 means we want to know the 6th term
an = 1/2 (4)^ (n-1)
We want to find the 6th term
a6 = 1/2 * 4^(6-1)
a6 = 1/2 * 4^5
a6 = 512