Ask question

Ask question

All categories

3 years ago

5

It took Jen, who biked at a speed of 12 mph, 20 minutes to get home. What is Jim’s speed, if it took him only 15 minutes to bike

that distance?

1 answer:

nataly862011 [7]3 years ago

8 0

1) Speed = 12mph =12 mi/1 h =12 mi/ 60 min = 1/5 mi/ min
1 h= 60 min
t =20 min
Distance=speed*time =1/5 *20 (mi/min *min)= 4 mi

2) If he would bike for 15 min
Distance=speed*time
speed = distance/time = 4mi/15 min =4 mi :(1/4 h)=4*4= 16 mi/h
15 min =1/4 h

You might be interested in

PLEASE HELP IM SERIOUSLY STUCK E

lara31 [8.8K]

Answer: 2.12 × $10^{-3}$

The coefficient (in green) will be 2.12

Step-by-step explanation:

Scientific notation is written by multiplying the number by a power of 10. This number is a number between 1 and 10.

Since this is a smaller number, we will be multiplying it by a power of 10 to a negative number.

To get this value to a number between 1 and 10, we must multiply it by 10 3 times (also shown as 10³) which gives us 2.12.

To get back to the original value, we multiply this by $10^{-3}$ . This gives us our answer.

3 0

2 years ago

Charlotte’s weekly paycheck is based on the number of hours worked during the week and on the weekend. If she works 13 hours dur

Gelneren [198K]

I am setting the week hourly rate to x, and the weekend to y. Here is how the equation is set up:

13x + 14y = $250.90
15x + 8y = $204.70

This is a system of equations, and we can solve it by multiplying the top equation by 4, and the bottom equation by -7. Now it equals:

52x + 56y = $1003.60
-105x - 56y = -$1432.90

Now we add these two equations together to get:

-53x = -$429.30 --> 53x = $429.30 --> (divide both sides by 53) x = 8.10. This is how much she makes per hour on a week day.

Now we can plug in our answer for x to find y. I am going to use the first equation, but you could use either.

$105.30 + 14y = $250.90. Subtract $105.30 from both sides --> 14y = $145.60 divide by 14 --> y = $10.40

Now we know that she makes $8.10 per hour on the week days, and $10.40 per hour on the weekends. Subtracting 8.1 from 10.4, we figure out that she makes $2.30 more per hour on the weekends than week days.

7 0

3 years ago

Read 2 more answers

Robert earns $25 per hour at work, and he works 8 hours a day. Paris earns $225 per day at work. They both work 40 hour work wee

Alisiya [41]

Answer: I believe Robert earns more

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers

Solve the following problems. Remember that all reasoning must be explained, and all steps of math work must be shown!

chubhunter [2.5K]

<h2>Question 1:</h2>

<h3>How to solve Part A</h3>

Since the diagram shows a right triangle and gives out some measurements of the sides, you can use the Pythagorean Theorem ( $a^{2}+b^{2}=c^{2}$ ) to find the length of MP.

<u>Given:</u>

hypotenuse = 7 – because the radius is 7 units and it can be used as the hypotenuse

One side of the triangle = 4 – because the length of PO is 4 units and it can be used as one sides of the triangle

<u>To Solve:</u>

Since we know two values of the triangle, you can use the Pythagorean Theorem ( $a^{2}+b^{2}=c^{2}$ ) to find what the other value is. The variables <em>c</em> and <em>b</em> in the formula are already given, and we need to find what <em>a</em> is to find the length of MP. So, plug the given values of <em>c</em> and <em>b</em> into the formula:

$a^{2}+4^{2}=7^{2}$

Simplify:

$a^{2}+16=49$

Subtract 16 from both sides of equation:

$a^{2}=33$

Do the square root of both sides to isolate the variable <em>a</em>:

$\sqrt{a^{2}}=\sqrt{33}$

Evaluate:

$a=\sqrt{33}$ Which simplifies to $a= 5.744562646....$ and round it to the nearest tenth to finally get $a=5.7$

Answer: The length of MP is 5.7 units

<h3>How to solve Part A</h3>

If you look at the diagram in the question, you can see that the length of MN is twice the length of MP. So multiply the length of MP, which is 5.7, by 2:

5.7 · 2 = 11.4

Answer: The length of MN is 11.4 units

___________________________________________________________

<h2>Question 2:</h2>

<h3>How to solve Part A</h3>

Look at the <u>first image</u> below ↓

<u>Description of the first image:</u>

The first image shows a drawn image of the circle with labeled parts and measurements from the infomation given from the question.

The diameter is 26cm, which means that the radius is 13cm because the radius half of the diameter in a circle. The very top line is the surface of the water where it’s filled and it has a length of 20cm. Side <em>b</em> of the triangle is 10cm becuase it’s half the length of the the surface of the water bowl. The hypotenuse (side <em>c</em>) is 13cm because it’s the length of the radius. And side <em>a </em>is what what we need to find because it’s the distance between the surface of the water and the center of the bowl. But after when you find the length of side <em>a</em>, you need to add the length of the radius (which is 13cm) to the length of side <em>a</em> because that’s the rest of the length/depth of the water that’s filled in the bowl. The length of the radius is included with the depth of the water.

<u>Total information given:</u>

⇒ radius = 13cm – because the radius is half of the diameter, and the diameter has a length of 26cm

⇒ length of the surface where the water’s filled = 20cm

⇒ hypotenuse (side <em>c</em>) = 13cm – because it’s the length of the radius

⇒ side <em>b</em> = 10cm – because it’s half the length of the surface where the water’s filled

<u>To Solve</u>

Since there is a right triangle shown in the image, you can use the Pythagorean Theorem ( $a^{2}+b^{2}=c^{2}$ ) to find the missing length of side <em>a</em>. Plug the given values of <em>c</em> and <em>b</em> into the formula:

$a^{2}+10^{2}=13^{2}$

Simplify:

$a^{2}+100=169$

Subtract 100 from both sides of the equation:

$a^{2}=69$

Do the square root of both sides to isolate the variable <em>a</em>:

$\sqrt{a^{2}}=\sqrt{69}$

Evaluate:

$a=\sqrt{69}$ Which simplifies to $a= 8.30662386....$ and round it to the nearest tenth to finally get $a$ ≈ $8.3$

This means that 8.3 is just the length of side <em>a</em>, which is the length between the surface of where the water’s filled and the center of the circle. But, now you need to add 13 to 8.3 to find the total depth of the water because the length of the radius is included with the depth of the water.

So,

13 + 8.3 = 21.3

Answer: The depth of the water is approximately 21.3 cm

<h3>How to solve Part B (is in the image below)</h3>

<em />

<em>Sorry for the very, VERY long explanation and the long solving process, but I really, really hope you understand and that this helps with your question! </em>:)

4 0

3 years ago

wariber [46]

Assuming you mean
$\lim_{x \to 4} \frac{\sqrt{x+5}-3}{4-x}$

that means as x approaches 4

if we sub 0 for x we get
0/0
and intermitent form
use l'hopital's rule

so
take the derivitive of the top and bottom seperatly
l'hopitals rule is something like
if $\lim_{x \to n} \frac{f(x)}{g(x)}$ results in 0/0 or -∞/∞ or∞/∞ then keep doing it until f(n)/g(n) gives a form that isn't intermitent

so

take derivitive of top and bottom
$\dfrac{\frac{1}{2\sqrt{x+5}}}{-1}$
now, if we subsitute 4 for x we get
$\dfrac{\frac{1}{2\sqrt{4+5}}}{-1}$ =

$\dfrac{\frac{1}{2\sqrt{9}}}{-1}$ =

$\dfrac{\frac{1}{2(3)}}{-1}$ =

$\dfrac{\frac{1}{6}}{-1}$ =

$\dfrac{1}{-6}=\dfrac{-1}{6}$

8 0

3 years ago