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3 years ago

9

Two trains leave stations 306 miles apart at the same time traveling toward each other one is traveling at 90 mph the other at 8

0 mph how long before they meet

1 answer:

Sergeu [11.5K]3 years ago

3 0

Answer:

They will meet in 1.8 hours.

Step-by-step explanation:

Given that, distance between trains = 306 miles

Let they take time $'t'$ to meet each other.

Speed of first train = 90 mph

Speed of second train = 80 mph

Let distance traveled by first train = $D_1$ miles

Formula for distance:

$Distance = Speed \times Time$

Distance traveled by first train, $D_1 = 90t$

Let distance traveled by first train = $D_2$ miles

Formula for distance:

$Distance = Speed \times Time$

Distance traveled by first train, $D_2 = 80t$

Total distance traveled is 306 miles.

i.e.

$D_1+D_2=306\\\Rightarrow 90t +80t=306\\\Rightarrow 170t=306\\\Rightarrow t =\dfrac{306}{170}\\\Rightarrow \bold{t=1.8\ hr}$

They will meet in 1.8 hours.

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Answer: There's an increasing interval between -1 and 1

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3 years ago

2x+3y=1 and y=-2 - 9 solve using linear combination method. Please explain steps.

kaheart [24]

Answer:

$x=17$

Step-by-step explanation:

$2x+3y=1$

$y=-2-9$

In order to combine these two equations, an idea you need to keep in mind is finding a way of setting these equations as equal to each other. I saw that each equation shared a common value, $y$ . In this case, we need to isolate $y$ in the first equation so that both equations $=y$ .

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With this, we now know that both $-2-9$ and $-\frac{2}{3}x+\frac{1}{3}$ are equal to $y$ , so we can set them equal to each other.

$y=-\frac{2}{3}x+\frac{1}{3}$

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$-\frac{2}{3}x+\frac{1}{3}=-11$

Reply to this if anything I'm saying or doing is confusing in any way, or if you find a mistake. :) Solve for $x$ .

$-\frac{2}{3}x+\frac{1}{3}=-11$

$-\frac{2}{3}x=-11-\frac{1}{3}$

$-\frac{2}{3}x =-\frac{33}{3}-\frac{1}{3}$

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Hopefully this answer is correct AND makes sense in terms of how I achieved it. Again, reply to this with any questions or mistakes I made and I'll do my best to answer or fix them.

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3 years ago

F(x) = x(x - 1)<br><br> g(x) = 3x<br> find (f*g)(6)

svetlana [45]

Step-by-step explanation:

<u>Given functions:</u>

f(x) = x(x - 1)
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<u>Find (f*g)(6):</u>

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<u>In case it is a composite function (f · g)(6) the answer is different:</u>

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2 years ago

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When the outlier is removed The mean would increase.

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Outliers are the value that lies outside the set of data. i.e. the data doesn't fit in the group.

Removing outliers can affect mean more than median. Because outlier removal sometimes affect the median but in a small percentage or sometimes it will remain the same.

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Mean = $\frac{1344}{16}$ .

Mean = 84.

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Mean = $\frac{84+82+86+84+85+83+86+82+85+84+83+86+85+86+85}{15}$ .

Mean = $\frac{1266}{15}$ .

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3 years ago

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Answer:

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This solution makes sense. Because 3 cups of flour produces 30 rolls, one cup produces 10 rolls. We need slightly more than 1 cup to get 12 rolls.

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2 years ago

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