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Studentka2010 [4]
2 years ago
9

The speed of a river current is 8 mph. If a boat travels 20 miles downstream in the same time that it takes to travel 10 miles​

upstream, find the speed of the boat in still water.
Mathematics
1 answer:
Rashid [163]2 years ago
8 0

Answer:

9 mph

Step-by-step explanation:

-Let x be the speed of the boat upstream.

-Since the time upstream and downstream is equal, we will equate their time functions to solve for x:

-Speed upstream=x-8

-Speed downstream=x+8

#We then equate as follows:

Time =\frac{Distance}{Speed}\\\\Time_1=Time_2\\\\\\\frac{10}{x-8}=\frac{20}{x+8}\\\\10(x+8)=20(x-8)\\\\10x+80=20x-160\\\\10x=240\\\\x=24\ mph

Hence, the speed of the boat in still water is 9 mph

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25to300 round to the nearest percent
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Answer:

163%

Step-by-step explanation:

Find in-between 25 and 300, which is 162.5 ,round to the nearest percentage being 163%. Hence your answer

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To assess the precision of a laboratory scale, we measure a block known to have a mass of 1 gram. we measure the block n times a
vlada-n [284]
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8 0
2 years ago
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Contact [7]

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I think this is the answer.

Hope this helps!

6 0
3 years ago
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Effectus [21]

Answer:

$3

Step-by-step explanation:

Original price - Discounted price

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So, the sale price is $3

<em>Hope it helps and is useful</em><em> </em><em>:</em><em>)</em>

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Answer:

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The line goes to the left so that means less than

x ≤5

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3 years ago
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