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2 years ago

Alexandra and her children went into a grocery store and she bought $7.65 worth of

Mathematics

1 answer:

zalisa [80]2 years ago

3 0

Answer:

$\large \boxed{\text{3 apples and 6 bananas}}$

Step-by-step explanation:

Let a = the number of apples

And b = the number of bananas. Then,

$\begin{array}{rcll}(1) \, 1.75a + 0.40 b & = & 7.65&\\(2)\, \, \, \, \quad \qquad a + b & = &9&\\(3) \, 0.40a + 0.40b & = &3.60&\text{Multiplied (2) by 0.40}\\1.35a & =&4.05\\(4) \, \, \quad \qquad \qquad a & =& \mathbf{3}&\text{Divided each side by 1.35}\\3 + b & = &9& \text{Substituted(4) into (2)}\\b &=& \mathbf{6}&\text{Subtracted 3 from each side}\\\end{array}\\\text{They bought $\large \boxed{\textbf{3 apples and 6 bananas}}$}$

Check:

$\begin{array}{cccl}3(1.75) + 6(0.40) = 7.65 & \qquad & 3 + 6 = 9\\5.25 + 2.40 = 7.65 & \qquad & 9 = 9\\7.65 = 7.65 & \qquad & \\\end{array}$

OK.

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There is a missing graph in the problem given. However, we can simply solve the equation using the given data.

Items to be sold: scarves and hats. Minimum of 20 items sold in all.
Scarves sell for 10 each and hats sell for 20 each. Must sell at least 300 worth of merchandise to make profit.

Let s represent scarves and h represent hats.

10s + 20h > 300
s + h > 20

We use inequality because the problem states "at least".

s + h = 20
10s + 20h = 300

s = 20 - h
10(20-h) + 20h = 300
200 - 10h + 20h = 300
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h = 100/10
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s = 20 - 10
s = 10

s + h > 20
10 + 10 > 20

10s + 20h > 300
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2 years ago

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Answer:

The formula to determine the population of penguins at the end of the 7th year is:

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Step-by-step explanation:

With this information, we know that the initial population at end of year 0 is 1000 penguins.

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We can then model the population for the end of year 1 as:

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As this dynamic will continue with the years, we can generalize as:

$P_2=1.3P_1=1.3\cdot (1.3P_0)=1.3^2P_0\\\\P_n=1.3^nP_0$

Then, the value of the population at the end of the 7th year should be:

$P_7=1.3^7\cdot P_0=6.275\cdot 1000=6275$

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2 years ago

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The degree of f(x) is 4. Also the leading coefficient is 1 and it is positive

So as x approaches infinity then y approaches infinity

as x approaches -infinity then y approaches infinity

The first and fourth graph goes up and it satisfies the above . so we ignore the second and third graph.

Now we check the x intercepts of the first graph

x intercepts of first graph is -4 and 2

Plug in -4 for x in f(x) and check whether we get 0

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$f(x)=(-4)^4+4(-4)^3-12(-4)^2-32(-4)+64=0$

Now plug in 2 for x and check

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So -4 and 2 are the x intercepts that satisfies f(x)

Hence first option is the graph of $f(x)=x^4+4x^3-12x^2-32x+64$

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Answer:

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