If it took you (one person) 3 days to build a doghouse, then it should take 2 people to build it in half the time. So all we have to do is split 3 days in 2.
3/2 = 1.5
So it would take 1 1/2 days or 36 hours for 2 people to complete the doghouse.
So the formula for the circumference of a circle is π x diameter
Since we know the the circumference already, we just divide that by π:
12π / π = 12
Now we halve the diameter to get the radius:
12 / 2 = 6
The area of a circle is π x radius²
So the area is:
·π x 6² = 36π· (or 113 not in terms of π)
Answer:
1,000 miles
Step-by-step explanation:
Maybe? Let me know if this helped
Answer: The input values are B-number of hours (x).
The output values are C-charge for babysitting(y).
The value of $10 represents the B-y intercept.
The value of $8 represents the C-slope.
Step-by-step explanation:
Charges to drive to the home= $10
Additional charges per hour=$8
Let x be the hour she worked (independent variable) and y be the total charge for baby sitting (dependent variable)
Thus, the input values are number of hours (x) and the output values are charge for babysitting(y)
According to the situation the equation would be
y=8x+10
which is equivalent to the slope intercept form y=mx+c, where
m=8, slope of line
At x=0, y=10
Thus, $10 represents the y intercept
<h2>9.</h2><h3>Given</h3>
<h3>Find</h3>
- linear approximation to the volume when the radius increases 0.4 cm
<h3>Solution</h3>
The equation for volume of a sphere is
... V = (4/3)π·r³
Differentiating gives
... dV = 4π·r²·dr
Filling in the given numbers gives
... change in volume ≈ 4π·(15 cm)²·(0.4 cm)
... = 360π cm³ ≈ 1130.97 cm³ . . . . . . volume of layer 4mm thick
<h2>11.</h2><h3>Given</h3>
- an x by x by 2x cuboid with surface area 129.6 cm²
- rate of change of x is 0.01 cm/s
<h3>Find</h3>
<h3>Solution</h3>
The area is that of two cubes of dimension x joined together. The area of each such cube is 6x², but the two joined faces don't count in the external surface area. Thus the area of the cuboid is 10x².
The volume of the cuboid is that of two cubes joined, so is 2x³. Then the rate of change of volume is
... dV/dt = (d/dt)(2x³) = 6x²·dx/dt
We know x² = A/10, where A is the area of the cuboid, so the rate of change of volume is ...
... dV/dt = (6/10)A·dx/dt = 0.6·(129.6 cm²)(0.01 cm/s)
... dV/dt = 0.7776 cm³/s
