If area is 36in² then multiply that by 6 as there are 6 faces
36 * 6 = 216in²
The diameter of the sphere is 60 mm which means its radius is 30mm. <span>The radius of a sphere is increasing at a rate of 5 mm/s.
The formula for the radius when the time is x second would be:
</span>r(t)<span>= 30+ 5x
dr/dt= 5
The speed of </span><span>volume increase </span><span>of the sphere volume would be derived from sphere volume:
</span>V(r)=4/3* pi * r^3<span>
dV/dt= 4/3 * pi * 3r^2 * (dr/dt) =4/3* pi * 3(30)^2 * 5 = 18000 pi= 56571 mm^3/s</span>
Answer:
b)4 11/10
Step-by-step explanation:
Answer:
the equation should be corrected to fit the data of the problem. With the corrected equation a mass of 0.5 grams remains after 150 years
Step-by-step explanation:
for the mass y( in grams)
y=23* (1/2)^(t/45), t ≥ 0.
the initial mass is at t=0 , then
y= 23 grams → should be 16 grams
half-life from the equation = 45 years → should be 30 years
the correct equation should be
y=16*(1/2)^(t/30), t ≥ 0
then after 150 years → t= 150
y=16*(1/2)^(150/30)= 16*(1/2)^5 = 16/32 = 0.5 grams
then a mass of 0.5 grams remains after 150 years
Answer:
20
Step-by-step explanation:
We write what we know.
Jimmy
$50/mo app 65¢ or .65
Lisa
$55/mo app 40¢ or .40
a = number of apps
The difference will come from the number of apps, a.
We need them to equal each other so let's write an equation.
$50 + .65a = $55 + .40a
We need to solve for a.
$50 + .65a = $55 + .40a subtract $50 for each side.
$50 - $50 + .65a = $55 - $50 + .40a
.65a = $55 - $50 + .40a
.65a = $5 + .40a subtract .40a from each side
.65a - .40a = $5 + .40a - .40a
.65a - .40a = $5
.25a = $5 Divide each side by .25
.25a/.25 = $5/.25
a = $5/.25
a = 20
So Jimmy and Lisa need to download 20 apps for their bill to be the same.
