3. The ratio of boys to girls in the math class is 5:8. If there are 40 girls, how

Mathematics

1 answer:

Butoxors [25]3 years ago

8 0

Answer:25 boys

Step-by-step explanation: look at pic below to see how solved.

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A bread recipe calls for a flour to water ratio of 10 to 7. If 600 grams of flour is used in this recipe, how many grams of wate

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Grams of water
= (600/10) x 7
= 420

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2 years ago

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Find d for the arithmetic series with S17=-170 and a1=2

Irina18 [472]

So, we know the sum of the first 17 terms is -170, thus S₁₇ = -170, and we also know the first term is 2, well

$\bf \textit{ sum of a finite arithmetic sequence}\\\\
S_n=\cfrac{n(a_1+a_n)}{2}\qquad 
\begin{cases}
n=n^{th}\ term\\
a_1=\textit{first term's value}\\
----------\\
n=17\\
S_{17}=-170\\
a_1=2
\end{cases}
\\\\\\
-170=\cfrac{17(2+a_{17})}{2}\implies \cfrac{-170}{17}=\cfrac{(2+a_{17})}{2}
\\\\\\
-10=\cfrac{(2+a_{17})}{2}\implies -20=2+a_{17}\implies -22=a_{17}$

well, since the 17th term is that much, let's check what "d" is then anyway,

$\bf n^{th}\textit{ term of an arithmetic sequence}\\\\
a_n=a_1+(n-1)d\qquad 
\begin{cases}
n=n^{th}\ term\\
a_1=\textit{first term's value}\\
d=\textit{common difference}\\
----------\\
n=17\\
a_{17}=-22\\
a_1=2
\end{cases}
\\\\\\
-22=2+(17-1)d\implies -22=2+16d\implies -24=16d
\\\\\\
\cfrac{-24}{16}=d\implies -\cfrac{3}{2}=d$

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Which of these angles are complementary?

lesya692 [45]

Answer: C. 45 degrees and 135 degrees

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Find the value of x so that the function has the givin value<br><br> n(x)=2x+7, n(x)=17

Sunny_sXe [5.5K]

Answer: x=5

Step-by-step explanation:

Substitute 17 for n(x)

17=2x+7

Subtract 7 from both sides

10=2x

Divide each side by 2 to get the x by itself

x=5

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RoseWind [281]

Answer:

c) -1

Step-by-step explanation:

-2-3-(-4)

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=-1

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3 years ago