Answer:
Tn = 64-4n
Step-by-step explanation:
The nth term of an AP is expressed as:
Tn = a+(n-1)d
a is the common difference
n is the number of terms
d is the common difference
Given the 6th term a6 = 40
T6 = a+(6-1)d
T6 = a+5d
40 = a+5d ... (1)
Given the 20th term a20 = -16
T20 = a+(20-1)d
T20 = a+19d
-16 = a+19d... (2)
Solving both equation simultaneously
40 = a+5d
-16 = a+19d
Subtracting both equation
40-(-16) = 5d-19d
56 = -14d
d = 56/-14
d = -4
Substituting d = -4 into equation
a+5d = 40
a+5(-4) = 40
a-20 = 40
a = 20+40
a = 60
Given a = 60, d = -4, to get the nth term of the sequence:
Tn = a+(n-1)d
Tn = 60+(n-1)(-4)
Tn = 60+(-4n+4)
Tn = 60-4n+4
Tn = 64-4n
Answer:
The water level is dropping at a rate of 0.24 ft/s
Step-by-step explanation:
Here, we simply want to calculate the change in depth (height of the cone) , given the volume change
Mathematically, we have the volume of a cone as;
V = 1/3 * π * r^2 * h
we are given dv/dt as 12 ft^3/m
dv/dh = 1/3 * π * r^2
Substituting the value for the radius, we have
dv/dh = 1/3 * 22/7 * 4^2 = 50.29
dh/dt = dh/dv * dv/dt
dh/dv = 1/(dv/dh) = 1/50.29
Thus,
dh/dt = 1/50.29 * 12
dh/dt = 0.24 ft/s
Answer:
1.33
Step-by-step explanation:
Answer:
115
Explanation:
Angles in a triangle sum to 180
Add the two angles given and subtract it from the total sum of angles to find the missing interior angle -
75 + 40 = 115
180 - 115 = 65
Now that we have the interior angle, we can work out the exterior angle by subtracting it from 180
180 - 65 = 115
