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3 years ago

10

In the first session 40 student attended.Of these 40 students 60% were girls. How many girls attended the first session of swimm

ing lessons?

2 answers:

Romashka-Z-Leto [24]3 years ago

8 0

24 girls

60% is 0.6
40 x 0.6 = 24

Nataliya [291]3 years ago

5 0

10% of 40 is 4.

4 x 6 = 24

There were 24 girls.

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Answer:

Dimensions of printed poster are

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width is 48 cm

Step-by-step explanation:

Let's assume

length of printed poster is x cm

width of printed poster is y cm

now, we can find area of printed poster

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so, we can set it to 1536

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now, we are given

The top and bottom margins of a poster are each 12 cm and the side margins are each 8 cm

so, total area of poster is

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now, we can plug back y

$A=(x+16)\times (\frac{1536}{x}+24)$

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so, we will find derivative

$A'=\frac{d}{dx}\left(\left(x+16\right)\left(\frac{1536}{x}+24\right)\right)$

we can use product rule

$A'=\frac{d}{dx}\left(x+16\right)\left(\frac{1536}{x}+24\right)+\frac{d}{dx}\left(\frac{1536}{x}+24\right)\left(x+16\right)$

$=\frac{d}{dx}\left(x+16\right)\left(\frac{1536}{x}+24\right)+\frac{d}{dx}\left(\frac{1536}{x}+24\right)\left(x+16\right)$

now, we can simplify it

$A'=-\frac{24576}{x^2}+24$

now, we can set it to 0

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$A'=-\frac{24576}{x^2}+24=0$

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$-24576+24x^2=0$

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4 years ago

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schepotkina [342]

Answer:

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Step-by-step explanation:

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Alex777 [14]

Answer:

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Food B=

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3 years ago