<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
Answer:
2 and -1 so it would be the first choice
A)
Step-by-step explanation:
Answer:
81/100
Step-by-step explanation:
Here's how to convert 0.81 to a fraction...
There is not much that can be done to figure out how to write 0.81 as a fraction, except to literally use what the decimal portion of your number, the .81, means.
Since there are 2 digits in 81, the very last digit is the "100th" decimal place.
So we can just say that .81 is the same as 81/100.
So your final answer is: 0.81 can be written as the fraction 81/100
1 1/3 + 1 1/6
add the 1 +1 = 2
add 1/3 + 1/6 ( find common denominator, which in this case is 6)
so 1/3 becomes 2/6
2/6 + 1/6 = 3/6 which reduces to 1/2
they ate 2 1/2 pints total
So you do 93 times 60 because it said you have to do 6 ten times and that equal 5580