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2 years ago

Need help! Can anyone please help me? It would be much appreciated. Please view the attached photo. Will mark as brainliest!

Mathematics

1 answer:

seraphim [82]2 years ago

6 0

Answer:

B) 0.0073 mm/s

Step-by-step explanation:

The rate of change of area is the product of the circumference and the rate of change of radius:

dA/dt = C·dr/dt

dr/dt = (dA/dt)/C

Of course, C = 2πr, so ...

dr/dt = (7 mm²/s)(2π·152 mm) ≈ 7/955.04 mm/s ≈ 0.0073 mm/s

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The number of members over time in an online music sharing club can be modeled by an exponential function. the club started with

Paraphin [41]

Answer:

a.) $N(x) = N_{0} e^{bx}$

b.) therefore b = $\ln \frac{2142}{2100} = \ln (1.02) = 0.0198$

b is the rate of increase of number of members

c.) The club will not be able to get more than 5000 members during its first year.

Step-by-step explanation:

i) the club started with 2100 members.

so we can write $N_{0}$ = 2100.

a.) so we can write the equation as an exponential function given by

$N(x) = N_{0} e^{bx}$ where x is in months and b is a constant and N(x) is the number of members in the online music sharing club .

therefore 2142 = 2100 $\times (e^{b\times 1})$ = 2100 $e^{b}$

b.) therefore b = $\ln \frac{2142}{2100} = \ln (1.02) = 0.0198$

b is the rate of increase of number of members

c.) Will the club have more than 5000 members during its first year? Justify your reasoning.

5000 = 2100 $e^{0.0198x}$

therefore x = $\frac{1}{0.0198} \ln{(\frac{5000}{2100} )} = 43.81 \hspace{0.1cm}months$

The club will not be able to get more than 5000 members during its first year.

7 0

2 years ago

What did Martina do to the equation 4x=2x + 402 to get 2x = 402

Tpy6a [65]

Step-by-step explanation:

she took the 2X and substract 4X-2X

the answer will be 2X=402

4 0

3 years ago

There are 3 red and 8 green balls in a bag. If you randomly choose balls one at a time, with replacement, what is the probabilit

Kaylis [27]

So, the total number of balls is 11. We want to pick 2 red balls and 1 green ball. WLOG (since order doesnt matter here), we can say he picks red, green, red. That means on his first pick, he has a $\frac{3}{11}$ chance of picking the red ball, and he places it back in the bag. The probability of picking a green ball is $\frac{8}{11}$ , and then he places the ball back in the bag. The probability of picking the last red ball is the same as the last red ball example, and we simply multiply the probabilities together as per the multiplication rule to get:

$\frac{3}{11}\frac{3}{11}\frac{8}{11}=\frac{3*3*8}{11^3}=\frac{72}{1331}$

Now, without replacement the order does matter. He picks a red ball, a red ball then a green ball. The probability of picking the first red ball is $\frac{2}{11}$ , and the probability of picking the second red ball is $\frac{1}{10}$ and the probability of picking the green ball is $\frac{1}{9}$ . We want to multiply thm again, as per the multiplication rule like the last problem.