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2 years ago

A student says that 3% is equal to 0.3 when written as a decimal. Is their thinking correct? Explain.

Mathematics

2 answers:

kakasveta [241]2 years ago

7 0

Answer:

Step-by-step explanation:

0.3 = 30% not 3%

to change a percentage to a decimal fraction, divide by 100

3% = $\frac{3}{100}$ = 0.03

madreJ [45]2 years ago

5 0

The answer is no.

Always remember when converting from percent to decimal, divide by 100%.

3% ÷ 100%
0.03 ≠ 0.3

Hence, the student's thinking is not correct.

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The mean is the average. Add up all the points, then divide by the number of points.

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c) $p_0 = 820-\frac{820}{e^6}$

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For this case we have the following differential equation:

$\frac{dp}{dt}=\frac{1}{2} (p-820)$

And if we rewrite the expression we got:

$\frac{dp}{p-820}= \frac{1}{2} dt$

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Using exponential on both sides we got:

$P= 820 + P_o e^{1/2t}$

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$770 = 820 + P_o e^0$

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So then our model would be given by:

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Part b

For this case we know that p(0) = p0 so we have this:

$p_0 = 820 + P_o e^0$

$P_o = p_0 -820$

So then our model would be given by:

$P(t) = (p_o -820)e^{1/2t} +820$

And if we want to find at which time the population would be extinct we have:

$0=(p_o -820)e^{1/2 t} +820$

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Using natural log on both sides we got:

$ln(-\frac{820}{p_0 -820}) = \frac{1}{2}t$

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$t = 2 *ln(-\frac{820}{p_0 -820})$

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