A boat starts at a point A. It travels a distance of 7 km on a bearing of 135° to point B. From B it

If you run for 0.4 hours at 7 mph, how fast should you walk during the next 0.8 hours to have the average speed of 5 mph?

Fantom [35]

Answer:

4 mph

Step-by-step explanation:

The average speed of an object is given by the total distance covered by the time taken:

$v=\frac{d}{t}$

where

d is the total distance covered

t is the time taken

in the first part, the person runs for 0.4 hours at a speed of 7 mph, so the distance covered in the 1st part is

$d_1 = v_1 t_1 = (7)(0.4)=2.8 mi$

Then the distance covered in the second part is $d_2$ , so the total distance is

$d=2.8+d_2$ (1)

The total time elapsed is 0.4 hours (first part) + 0.8 hours (second part), so

$t=0.4+0.8=1.2 h$

So we can write the average speed as

$v=\frac{2.8+d_2}{1.2}$ (1)

We want the average speed to be 5 mph,

v = 5 mph

Therefore we can rearrange eq.(1) to find d2:

$d_2 = 1.2v-2.8 = (1.2)(5)-2.8=3.2 mi$

And therefore, the speed in the second part must be

$v_2=\frac{d_2}{t_2}=\frac{3.2}{0.8}=4 mph$

4 0

3 years ago

What expression is equivalent to 27 + 15?

Natali [406]

You should try this (20+7)+(10+5)=42

6 0

3 years ago

HEY GUYS I NEED THIS ANSWER NOW

Sergio [31]

Let

x-------> the number of fiction books

y-------> the number of nonfiction books.

we know that

$x+y=26$ -----> equation $1$

$x=y+12$

$x-y=12$ -----> equation $2$

Add equation $1$ and equation $2$

$x+y=26\\x-y=12\\ ------\\ 2x=38\\ x=38/2\\x=19\ fiction\ books$

find the value of y

$x+y=26$

$19+y=26$

$y=26-19=7\ nonfiction\ books$

therefore

the answer is

Part a) the number of fiction books is $19\ fiction\ books$

Part b) the number of nonfiction books is $7\ nonfiction\ books$

6 0

3 years ago

Read 2 more answers

The steps to solve this problem

Free_Kalibri [48]

I can't see an imagine I'm really sprry

4 0

3 years ago

Rule y = x - 3 plz help me :(

Andru [333]

<h3>The answer!</h3>

<h3>Lets do the Solve the equetion first!</h3>

<h3>Solution:</h3><h3> $y = x - 3 \\ = y - x = - 3 \\ = - x = - 3 - y \\ = - x = - y - 3 \\ = x = y + 3$ </h3><h3>The answer is </h3><h3> $x = y + 3$ </h3><h3>꧁✰_______❀Edilyn❀_______✰꧂</h3><h3 />

#CarryOnLearning

#NoToCopyPaste

<h3>Correct me if im wrong</h3>

Its base on my understanding

<h3>For brainly user:</h3>

Just please, idols ,if we are going to answer questions here on brainly, don't do the ones from the internet, then just copy and paste

Just please, idols ,if we are going to answer questions here on brainly, don't do the ones from the internet, then just copy and paste You can search on the internet but make your own sentence okay? Thank you

Please dont delete this:((

7 0

3 years ago