Find amount used:
Amount in the card = $20
Amount left = $13.28
Amount used = $20 - $13.28 = $6.72
Find duration of the call:
24 cents = 1 min
672 cents = 1/24 x 672 = 28 mins
Answer: The call was 28 minutes long.
Answer:
(x + 1)^2 + (y - 1)^2 = 74
Step-by-step explanation:
By looking at the graph, we can see the center of the circle is (-1, 1).
Next, we can find the radius. We are given the point (6, -4) is on the circle. The distance from the center to a point on a circle is the radius. We can plug the points (-1, 1) and (6, -4) into the distance formula to get the radius:
r = √([-1-6]^2 + [1-(-4)]^2)
r = √(49 + 25)
r = √74
The equation of a circle is denoted in the form:
(x - h)^2 + (y - k)^2 = r^2
where (h, k) is the center and r is the radius.
We can plug in the values we calculated:
(x + 1)^2 + (y - 1)^2 = 74
18.273 years will take to reach the population of 7500, if a town has a population of 4000 and grows at 3.5% every year.
Step-by-step explanation:
The given is,
Population of 4000
Rate of grow 3.5% every year
Population after few years 7500
Step:1
Formula to calculate the population with the grow rate every year,
..........................(1)
Where,
F - Population after t years
P - Initial population
r - Rate of grow
t - No.of years
From given,
F = 7500
P = 4000
r = 3.5%
Equation becomes (1),


1.875 = 

Take log on both sides,

Substitute log values,


= 18.273
t = 18.273 year
or
t = 18 years 3 months 2 weeks
Result:
18.273 years will take to reach the population of 7500, if a town has a population of 4000 and grows at 3.5% every year.
Answer:
5 pt
Step-by-step explanation: