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alexdok [17]
4 years ago
13

Please Help!!!! Will mark brainliest. Thank you so much for your help

Mathematics
1 answer:
matrenka [14]4 years ago
8 0

Answer:

a)

y=400(2.5)^{x}

b)

3,814,698

c)

16.08 weeks

Step-by-step explanation:

a)

The question presented here is similar to a compound interest problem. We are informed that there are 400 rice weevils at the beginning of the study. In a compound interest problem this value would be our Principal.

P = 400

Moreover, the population is expected to grow at a rate of 150% every week. This is equivalent to a rate of interest in a compound interest problem.

r = 150% = 1.5

The compound interest formula is given as;

A=P(1+r)^{n}

We let y be the weevil population in any given week x. The formula that can be used to predict the weevil population is thus;

y=400(1+1.5)^{x}\\\\y=400(2.5)^{x}

b)

The weevil population 10 weeks after the beginning of the study is simply the value of y when x = 10. We substitute x with 10 in the equation obtained from a) above;

y=400(2.5)^{10}\\\\y=3814697.3

Therefore, the weevil population 10 weeks after the beginning of the study is approximately 3,814,698

c)

We are simply required to determine the value of x when y is

1,000,000,000

Substitute y with 1,000,000,000 in the equation obtained in a) above and solve for x;

1000000000=400(2.5)^{x}\\\\2.5^{x}=2500000\\\\xln(2.5)=ln(2500000)\\\\x=\frac{ln(2500000}{ln(2.5)}=16.0776

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Step-by-step explanation:

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