The boat went 5hours upstream, let's say it has a "still water" speed rate of "b", it went 100miles... however, going upstream is going against the current, let's say the current has a speed rate of "c"

so, when the boat was going up, it wasn't really going "b" fast, it was going " b - c " fast, because the current was eroding speed from it

now, when coming down, the return trip, well the length is the same, so the distance is also 100miles, it only took 2hrs though, because, the boat wasn't coming down "b" fast, it was coming down " b + c " fast, because the current was adding speed to it, so it came down quicker

now, recall your d = rt, distance = rate * time

$\bf \begin{array}{lccclll}
&distance&rate&time\\
&-----&-----&-----\\
upstream&100&b-c&5\\
downstream&100&b+c&2
\end{array}
\\\\\\
\begin{cases}
100=(b-c)5\\
\qquad \frac{100}{5}=b-c\\
\qquad 20=b-c\\
\qquad 20+c=\boxed{b}\\
100=(b+c)2\\
\qquad 50=b+c\\
\qquad 50=\boxed{20+c}+c
\end{cases}$

solve for "c", to see what's the current's speed

what's "b"? well 20+c = b

4 0

3 years ago

1. The following set of numbers is going to be graphed on a histogram.

statuscvo [17]

Answer:

i have the same question pls help us

Step-by-step explanation:

4 0

3 years ago

A circle is a set of all points that are the same distance from one given point. Find an wxample that cotradicts this definition

eduard

Answer:

Part A

The given definition of a circle is the set of all points that are the same distance from one given point

One example that contradicts the definition, is the set of all points in a three dimensional plane which are equidistant from, a point, which is the definition of a sphere

Part B

The definition of a circle can be modified to include the location of the points <em>on the same plane</em>, from which we therefore have;

<em>A circle is a set of all points on a plane that are the same distance from one given point</em>

Step-by-step explanation:

7 0

3 years ago