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Natasha_Volkova [10]
2 years ago
15

Emily reads a story book. o the first day, she reads 1/9 of the whole book, and on the second day, she reads 24 pages. The ratio

of the number of pages read to the remaining pages in the two days is 1:4. How many pages are there in this book
Mathematics
2 answers:
Marina86 [1]2 years ago
8 0

There are 270 pages in this book.

Given that,

Emily reads a storybook the first day,

She reads 1/9 of the whole book, and on the second day, she reads 24 pages.

The ratio of the number of pages read to the remaining pages in the two days is 1:4.

We have to find

How many pages are there in this book?

According to the question,

Let, P is the number of pages,

The first day Emily reads p/9 pages of the whole book,

And the second day she read 24 pages.

The ratio of the number of pages read to the remaining pages in the two days = 1;4 = p/5.

Therefore,

The number of pages reads first day + the number of pages read the second day = The ratio of the number of pages read to the remaining pages in the two days

\rm \dfrac{p}{9} + 24 = \dfrac{p}{5}\\\\ \dfrac{p}{5} - \dfrac{p}{9} = 24\\\\\dfrac{p \times 9 - p\times 5}{45} = 24\\\\ \dfrac{9p-5p}{45} = 24\\\\\dfrac{4p}{45} = 24\\\\4p = 24\times 45\\\\4p = 1080\\\\p = \dfrac{1080}{4}\\\\p = 270 \ pages

Hence, there are 270 pages in this book.

For more details refer to the link given below.

brainly.com/question/14505922

Liula [17]2 years ago
4 0

Answer:

Step-by-step explanation:

Let P be the number of pages

First day reads P/9 pages

Second day reads 24 pages

two days reading is P/5  (1 page read for every 4 pages left)

         P/9 + 24 = P/5

        P + 24(9) = 9P/5

  5P + 24(9)(5) = 9P

               1080 = 4P

                     P = 270 pages

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We then have, using the power and chain rules,

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For the third function, we first rewrite in terms of the logarithmic and the exponential functions,

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Then by the chain rule,

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By the product rule, we have

\displaystyle \frac{dy}{dx} = \frac{df}{dx}gh + f\frac{dg}{dx}h + fg\frac{dh}{dx}

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You could simplify this further if you like.

In Mathematica, you can confirm this by running

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