Dr /dt = 7
A = pi r^2
dA / dr = 2pir
dA/dt = dA/dr * dr/dt = 2pir * 7 = 14pir
when r = 12 rate of change of the area = 14*pi*12 = 168pi
= 527.79 cm^2 / minute to nearest hundredth
Probability is defined as the <u>likelihood or the certainty</u> that an event is going to<u> occur or happen.</u>
The probability of randomly choosing a red and then a green marble is
.
The total number of marbles = 20
The number of green marbles= 3
The number of blue marbles = 12
The number of red marbles = 5
<u>The probability of choosing a red marble</u> = Number of red marbles / Total number of marbles
= 5/20
<u>In simplest fraction form</u> = 
We are told in the question that you keep the red marble you choose, So this means the <u>total number of marbles</u> left reduces to 19
<u>The probability of choosing a green marble is</u> = Number of green marbles / New total number of marbles
= 3/19
Therefore, <u><em>the probability of randomly choosing a red and then a green marble is </em></u>
P (Red) x P(Green)
= 1/4 x 3/19
= 
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Answer:
y=6
Step-by-step explanation:
7y+6=18-5y
-5y, -6
2y=12
y=6