1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ruslelena [56]
3 years ago
9

Two tourists went on a hike at dawn. One went from a to b and another one went from b to a. They met at noon but did not stop an

d continued walking maintaining same speed for the whole trip. One finished his hike at 4pm in B and another one came to A at 9 pm. At what hour was dawn that day?
Mathematics
1 answer:
Alecsey [184]3 years ago
8 0
<span>Dawn was at 6 am. Variables a = distance from a to passing point b = distance from b to passing point c = speed of hiker 1 d = speed of hiker 2 x = number of hours prior to noon when dawn is The first hiker travels for x hours to cover distance a, and the 2nd hiker then takes 9 hours to cover that same distance. This can be expressed as a = cx = 9d cx = 9d x = 9d/c The second hiker travels for x hours to cover distance b, and the 1st hiker then takes 4 hours to cover than same distance. Expressed as b = dx = 4c dx = 4c x = 4c/d We now have two expressions for x, set them equal to each other. 9d/c = 4c/d Multiply both sides by d 9d^2/c = 4c Divide both sides by c 9d^2/c^2 = 4 Interesting... Both sides are exact squares. Take the square root of both sides 3d/c = 2 d/c = 2/3 We now know the ratio of the speeds of the two hikers. Let's see what X is now. x = 9d/c = 9*2/3 = 18/3 = 6 x = 4c/d = 4*3/2 = 12/2 = 6 Both expressions for x, claim x to be 6 hours. And 6 hours prior to noon is 6am. We don't know the actual speeds of the two hikers, nor how far they actually walked. But we do know their relative speeds. And that's enough to figure out when dawn was.</span>
You might be interested in
I only have 10 minutes left!! I need to know the answer!!! <br> I WILL MARL BRAINLY
Advocard [28]

Answer:

x<1

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
Note: Figure not drawn to scale.
ycow [4]

Answer:

this is very simple

its 2342423424324343

Step-by-step explanation:

4 0
3 years ago
a set of measuring cups has measures of 1 cup, 3/4 cup, 1/2 cup, 1/3 cup, and 1/4 cup. How could I measure 1/6 of a cup using th
Sophie [7]

1/2 cup = 3/6 cup

1/3 cup =2/6 cup

Just dump a much from the 1/2 cup into the 1/3 cup.

The 1/2 cup will have 1/6 left.

7 0
3 years ago
The measurenicnt of the circumference of a circle is found to be 56 centimeters. The possible error in measuring the circumferen
BartSMP [9]

Answer:

(a) Approximate the percent error in computing the area of the circle: 4.5%

(b) Estimate the maximum allowable percent error in measuring the circumference if the error in computing the area cannot exceed 3%: 0.6 cm

Step-by-step explanation:

(a)

First we need to calculate the radius from the circumference:

c=2\pi r\\r=\frac{c}{2\pi } \\c=8.9 cm

I leave only one decimal as we need to keep significative figures

Now we proceed to calculate the error for the radius:

\Delta r=\frac{dt}{dc} \Delta c\\\\\frac{dt}{dc} =    \frac{1}{2 \pi } \\\\\Delta r=\frac{1}{2 \pi } (1.2)\\\\\Delta r= 0.2 cm

r = 8.9 \pm 0.2 cm

Again only one decimal because the significative figures

Now that we have the radius, we can calculate the area and the error:

A=\pi r^{2}\\A=249 cm^{2}

Then we calculate the error:

\Delta A= (\frac{dA}{dr} ) \Delta r\\\\\Delta A= 2\pi r \Delta r\\\\\Delta A= 11.2 cm^{2}

A=249 \pm 11.2 cm^{2}

Now we proceed to calculate the percent error:

\%e =\frac{\Delta A}{A} *100\\\\\%e =\frac{11.2}{249} *100\\\\\%e =4.5\%

(b)

With the previous values and equations, now we set our error in 3%, so we just go back changing the values:

\%e =\frac{\Delta A}{A} *100\\\\3\%=\frac{\Delta A}{249} *100\\\\\Delta A =7.5 cm^{2}

Now we calculate the error for the radius:

\Delta r= \frac{\Delta A}{2 \pi r}\\\\\Delta r= \frac{7.5}{2 \pi 8.9}\\\\\Delta r= 0.1 cm

Now we proceed with the error for the circumference:

\Delta c= \frac{\Delta r}{\frac{1}{2\pi }} = 2\pi \Delta r\\\\\Delta c= 2\pi 0.1\\\\\Delta c= 0.6 cm

5 0
3 years ago
Me + You = Friends :))
Stolb23 [73]

Answer:

yes

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
Other questions:
  • Which of the following terms correctly describe the figure given below? Check all that apply.
    10·2 answers
  • The circumference of circle A is twice the circumference of circle B. Which statement about the areas of the circles is true?
    10·2 answers
  • Can this visual be described with a linear, exponential, or neither
    9·1 answer
  • 15 POINTS AND BRAINLIEST ANSWER!!
    7·2 answers
  • 16 factory workers made 40 pieces in a certain amount of time.
    10·1 answer
  • Log(8)a/2. Expand the logarithmic expression.
    10·1 answer
  • Name 21 and 22 another way.
    9·1 answer
  • Identify the domain of the exponential function shown in the following graph:
    8·2 answers
  • The angle measurements in the diagram are represented by the following expressions.
    15·2 answers
  • Help :) Answer this fast plss
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!