Marcy played the piano for 45 minutes.She stopped playing at 4:15 P.M.At what time did she start playing the piano

Ann [662]

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Question
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$\boxed { \frac{n+h}{5} = \frac{f+9}{9}}$

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Split the fraction on the left
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$\boxed { \frac{n}{5} + \frac{h}{5} = \frac{f + 9}{9}}$

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Take away h/5 from both sides
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$\boxed { \frac{n}{5} = \frac{f+9}{9} - \frac{h}{5}}$

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Change the denominator to be the same
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$\boxed { \frac{n}{5} = \frac{5f+45}{45} - \frac{9h}{45}}$

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Put it into single fraction
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$\boxed { \frac{n}{5} = \frac{5f+45-9h}{45} }$

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Rearrange (This step may not be necessary)
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$\boxed {\frac{n}{5} = \frac{5f-9h+ 45}{45} }$

$\bf \Longrightarrow \ Answer \ : \boxed {\boxed {\frac{n}{5} = \frac{5f-9h+ 45}{45} }}$

6 0

2 years ago

A cube has a volume of 3375 cubic units calculate the length of one side of the cube

8090 [49]

Answer:

volume = length^3

3375= length^3

therefore length = 15 units

3 0

1 year ago

The city is planning to add a fish pound to a neighborhood park. the figure below is a scale drawing of the fish pound. its scal

CaHeK987 [17]

Answer: Sorry if it's wrong I hope I helped you

5 0

1 year ago

In a population distribution, a score of x=57 corresponds to z=-0.25 and a score of x=87 corresponds to z=1.25. Find the mean an

Serggg [28]

Here is dependence between scores and x-values:

$Z_i=\dfrac{X_i-\mu}{\sigma},$

where $\mu$ is the mean, $\sigma$ is standard deviation and i changes from 1 to 2.

1. When i=1, $Z_1=-0.25,\ X_1=57,$ then

$-0.25=\dfrac{57-\mu}{\sigma}.$

2. When i=2, $Z_2=1.25,\ X_2=87,$ then

$1.25=\dfrac{87-\mu}{\sigma}.$

Now solve the system of equations:

$\left\{\begin{array}{l}-0.25=\dfrac{57-\mu}{\sigma}\\ \\1.25=\dfrac{87-\mu}{\sigma}.\end{array}\right.$

$\left\{\begin{array}{l}-0.25\sigma=57-\mu\\ \\1.25\sigma=87-\mu.\end{array}\right.$

Subtract first equation from the second:

$1.25\sigma-(-0.25\sigma)=87-57,\\ \\1.5\sigma=30,\\ \\\sigma=20.$

Then

$1.25=\dfrac{87-\mu}{20},\\ \\87-\mu=25,\\ \\\mu=87-25=62.$

Answer: the mean is 62, the standard deviation is 20.

3 0

3 years ago

Read 2 more answers

Murad ran in a track race on Tuesday he finished the race in 420 seconds how many minutes did it take to run the race?

max2010maxim [7]

The key information here is the time he took to run the race - 420 seconds

We know that there are 60 seconds in 1 minute so to find the number of minutes we divide 420 by 60 to get 7.

Murad took 7 minutes to run the race

7 0

3 years ago

Read 2 more answers