Answer: the remaining credit after 79 minutes of call is $15.52
Step-by-step explanation:
let x represent the number of minutes of call.
Let y represent the remaining credit after x minutes of call.
If we plot y on the vertical axis and x on the horizontal axis, a straight line would be formed. The slope of the straight line would be
Slope, m = (17.2 - 19.84)/(65 - 43)
m = - 2.64/22 = - 0.12
The equation of the straight line can be represented in the slope-intercept form, y = mx + c
Where
c = intercept
m = slope
To determine the intercept, we would substitute x = 65, y = 17.2 and m = - 0.12 into y = mx + c. It becomes
17.2 = - 0.12 × 65 + c
17.2 = - 7.8 + c
c = 17.2 + 7.8
c = 25
The linear function becomes
y = - 0.12x + 25
Therefore, the remaining credit after 79 minutes of call is
y = - 0.12 × 79 + 25
y = - 9.4 + 25
y = 15.52
Cross sections of the volume are washers or annuli with outer radii <em>x(y)</em> + 1, where
<em>y</em> = <em>x(y) </em>² - 1 ==> <em>x(y)</em> = √(<em>y</em> + 1)
and inner radii 1. The distance between the outermost edge of each shell to the axis of revolution is then 1 + √(<em>y</em> + 1), and the distance between the innermost edge of <em>R</em> on the <em>y</em>-axis to the axis of revolution is 1.
For each value of <em>y</em> in the interval [-1, 3], the corresponding cross section has an area of
<em>π</em> (1 + √(<em>y</em> + 1))² - <em>π</em> (1)² = <em>π</em> (2√(<em>y</em> + 1) + <em>y</em> + 1)
Then the volume of the solid is the integral of this area over [-1, 3]:
<span> $947.50
</span> - $189.50
_________
$758.00
So, to do this first we start at the far right and go to the left.
$947.50 - $189.50_________
$ .00
0-0= 0
5-5= 0
You then bring down the decimal.
$947.50 - $189.50_________
$ 8 .00
Because you cannot subtract 9 from 7, you borrow one from the number to the left of it and 7 turns into a 17 as 4 turns into a 3. So then, 17-9=8.
17
$93-7-.50 -7- = This means the 7 has been canceled out and turned - $189.50 into the 17 above _________ 8 .00
This happens again with subtracting 3 from 8 in which you take one from the number beside which happens to be 9 and make it 8.
17
$8-3--7-.50 -7- and -3- = This means the 7 has been canceled out and turned into the 17 above
- $189.50 _________ $ 58 .00
So then, 13-8=5. Finally 8-1= 7
$947.50
- $189.50
_________
$758.00
30,60,90,120
40,80,120
they will both " ash " in 120 seconds (thats 2 minutes)...so they will both ash at
10:42 a.m.
Just add them all up and divide by how many numbers there are
6+12+22+16=56
56 divided by 4 = 14
14 is the mean
