Melinda and Paul shovel driveways and sidewalks in the winter as a way to earn extra money. Together they shoveled 450 square feet of sidewalk in 30 minutes. Then Melinda shoveled for 20 minutes while Paul shoveled for 25 minutes to complete 345 square feet of driveway. 30x + 30y = 450 20x + 25y = 345 How much more can Paul shovel in 1 minute than Melinda? 3 square feet per minute 6 square feet per minute 9 square feet per minute 15 square feet per minute

QUESTION POSTED AT 18/01/2020 - 06:36 AM

Answered by admin AT 18/01/2020 - 06:36 AM

Answer: Hello mate!

we have the system of equations

30x + 30y = 450

20x + 25y = 345

where x is the number of square feet of snow that Melinda shovels in one minute, and y is the number of square feet of snow that Paul shovels in one minute.

Let's solve the system of equations, first, isolate one of the therms in the first equation, for example, x.

30x+30y = 450

x + y = 450/30 = 15

x = 15 - y

now we can replace it in the second equation and solve it for y.

20x + 25y = 345

20(15 - y) + 25y = 345

300 - 20y + 25y = 345

5y = 45

y = 45/5 = 9

Paul can shovel 9 square feets of snow in one minute, now replace it in the first equation and solve it for x.

x + y = 450/30 = 15

x + 9 = 15

x = 15 - 9 = 6

so melinda sholves 6 square feet of snow in one minute.

The question is:

How much more can Paul shovel in 1 minute than Melinda?

We need to see the difference y - x = 9 - 6 = 3

this means that paul shovels 3 more square feet per minute than Melinda.

Post your answer

Related questions

14.A company employee has to print 3145 pages, and the company's printer prints 85 pages per minute. The function f(x)=−85x+3145f(x)=−85x+3145 represents the number of unprinted pages x minutes after the printing begins. What is the practical domain of function f? all whole numbers from 0 to 37 all real numbers from 0 to 37 all real numbers from 0 to 3145 all multiples of 85 between 0 and 3145

F(x) = -85x + 3145...the domain is going to be the x value while the range is the f(x) value.

answer is going to be all whole numbers from 0 to 37

notice if u sub in 37 for x.....
f(37) = -85(37) + 3145
f(37) = - 3145 + 3145
f(37) = 0...that means after 37 minutes, there are no un-printed pages...all the pages have been printed. So ur answer would be greater then 0, but less then or equal to 37.....and they have to be whole numbers.....they cant be all real number because that includes irrational numbers.

ANSWERED AT 16/02/2020 - 07:04 PM


QUESTION POSTED AT 16/02/2020 - 07:04 PM

What is the conjugate of the square root of -15 ? ...?

The answer to the problem is as follows:


The square root of -15 is equal to i*sqrt(15). Therefore, the conjugate of this complex number is -i*sqrt(15).


I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!



ANSWERED AT 16/02/2020 - 06:43 PM


QUESTION POSTED AT 16/02/2020 - 06:43 PM

Which of the following represents the set of possible rational roots for the polynomial shown below? 2x³+5x²-8x-10=0 a. {±2/5, ±1/2, ±1, ±2, ±2/5, ±1/5, ±1/10} b. {±1/2, ±1, ±2, ±5/2, ±5, ±10} c. {±1, ±2, ±4, ±5, ±10, ±20} d. {1/2, 1, 2, 5/2, 4, 5, 10, 20} ...?

Answer:

Option b is correct

Step-by-step explanation:

Given the polynomial

2x^3+5x^2-8x-10=0

we have to find the set of possible rational roots for the polynomial.

Rational root theorem states that if P(x)  has any rational roots then they must be of form

\pm{\frac{\text{Factor of }a_0}{\text{factors of }a_n}

Here P(x)=2x^3+5x^2-8x-10

Factors of 10=1, 2, 5, 10

Factors of 2=1, 2

Possible rational roots are

\{\pm1, \pm\frac{1}{2}, \pm2, \pm\frac{5}{1}, \pm\frac{5}{2}, \pm 10\}

Option b is correct

ANSWERED AT 16/02/2020 - 06:41 PM


QUESTION POSTED AT 16/02/2020 - 06:41 PM

What is the quotient: (3x2 + 4x – 15) ÷ (x + 3) ? is it 3x – 1, r = 1? i would just like for someone to confirm if it is or isnt ...?

Answer:

No, it is 3x-5 and r=0

Step-by-step explanation:

We can do it by long division method  the required quotient is 3x-5 and r=0

not 3x-1 , r=1

multiply the divisor with 3x  we will get 3x^2+9xto cancel out the first term of dividend

Now after solving we will get -5x-15

Now, multiply the divisor by -5 we will get -5x-15 which will cancel the entire dividend.

ANSWERED AT 16/02/2020 - 06:37 PM


QUESTION POSTED AT 16/02/2020 - 06:37 PM

If there is 123 trees and 15% is you land how much is the rest

Well 15% of 123 is 18.45, so that's how much you own. 81.55% is the trees you don't own.

ANSWERED AT 16/02/2020 - 06:23 PM


QUESTION POSTED AT 16/02/2020 - 06:23 PM

Matthew practices his violin for 25th minutes a day.he started at 3:15.what time will it be when Matthew stops practicingA. 3:30B. 3:40C. 3:50D. 4:50


B. 3:40
You would have to add 25 minutes to 3:15 to get 3:40

ANSWERED AT 16/02/2020 - 06:21 PM


QUESTION POSTED AT 16/02/2020 - 06:21 PM

Find two numbers whose sum is 30, and whose difference is 26

Yea umm Im not sure but 2, 28?

ANSWERED AT 16/02/2020 - 06:02 PM


QUESTION POSTED AT 16/02/2020 - 06:02 PM

Factor completely 3x2 + 9x – 54. ...?

3x² + 9x - 54 :(3)
x² + 3x - 18
(x-3)*(x+6)

ANSWERED AT 16/02/2020 - 05:43 PM


QUESTION POSTED AT 16/02/2020 - 05:43 PM

When working with the square root of a number, when would you have only a positive answer and when would you have both a positive and negative answer?

Lets make it clear: You would have a positive answer when the value you are looking for has to be a positive number. On the other hand you would have a positive and a negative answer when you take the square root of something that doesn't have to be positive. it could be either because when a negative number is squared it becomes positive and when a positive number is squared it stays positive as well.

ANSWERED AT 16/02/2020 - 05:24 PM


QUESTION POSTED AT 16/02/2020 - 05:24 PM

Suzanne is going to rent a car while she is out of town. One car rental company offers a flat rate of $35 per day plus $0.10 per mile. Another car rental company offers the same car for $25 per day plus $0.25 per mile. She will need the car for 5 days. How many miles would she need to drive for the first rental company to be a better deal?

Answer:

She need to drive more than 2000 miles for the first rental company to be a better deal .

Step-by-step explanation:

Case 1) One car rental company offers a flat rate of $35 per day plus $0.10 per mile

Let m be the no. of miles

She will need the car for 5 days.

So, total cost = 35 \times 5 +0.10m=175+0.10m

Case 2)  Another car rental company offers the same car for $25 per day plus $0.25 per mile.

Let m be the no. of miles

She will need the car for 5 days.

So, total cost = 25 \times 5 +0.25m=125
+0.25m

Now we are supposed to find How many miles would she need to drive for the first rental company to be a better deal?

So, 175+0.10m <125&#10;+0.25m

175+125 <125&#10;+0.25m-0.10m

300 < 0.15m

\frac{300}{0.15} < m

2000 < m

So, she need to drive more than 2000 miles for the first rental company to be a better deal

ANSWERED AT 16/02/2020 - 05:24 PM


QUESTION POSTED AT 16/02/2020 - 05:24 PM

A quantity is growing at a constant 3% yearly rate.what would be it's percent growth after 15 years?

45% because you have to multiply 3% by 15 years

ANSWERED AT 16/02/2020 - 05:16 PM


QUESTION POSTED AT 16/02/2020 - 05:16 PM

Miguel hiked 3 miles in 54 minutes. at this rate, how long will it take him to hike 5 miles?

Answer:

For 5 miles Miguel takes 90 minutes.

Step-by-step explanation:

As given

Miguel hiked 3 miles in 54 minutes.

i.e

3 miles = 54 minUtes

\frac{54}{3}\ minutes = 1\ miles

18 minutes = 1 miles

Thus

For 1 miles Miguel takes 18 minutes.

Now calculated for 5 miles.

Time\ taken\ for\ 5\ miles = 18\times 5

Time\ taken\ for\ 5\ miles =90\ minutes

Therefore for 5 miles Miguel takes 90 minutes.



ANSWERED AT 16/02/2020 - 04:52 PM


QUESTION POSTED AT 16/02/2020 - 04:52 PM

If x = 4 calculate the value of x squared 2x

x² × 2x = 16 × 8 = 128

ANSWERED AT 16/02/2020 - 04:51 PM


QUESTION POSTED AT 16/02/2020 - 04:51 PM

What is the square root of 97? for my younger friend

Square root of 97 is originally 9.848857802 when you punch it in a calculator , so you have to move the decimal two loops to the right which gives you 9.84 & that's the square root of 97 :)

ANSWERED AT 16/02/2020 - 04:39 PM


QUESTION POSTED AT 16/02/2020 - 04:39 PM

A chemistry student needs to make 60 liters of a 30% alcohol solution. He has a 20% alcohol solution and a 40% alcohol solution in the lab. How many liters of each strength does he need to mix together *The system of equations I did was: a+b=60 & .2a+.4b=18. I may be wrong but i seriously need help

Hi i am sorry i am not sure what to do here i mainly answer questions in biology and maths so if u have any questions related to that subject u can ask me but chemsitry i am not really good at sorry xx

ANSWERED AT 16/02/2020 - 04:20 PM


QUESTION POSTED AT 16/02/2020 - 04:20 PM

find a ratio equivalent to each ratio ` then use the ratios to write a proportion * 1) 22 / 30 2) 7 / 9 3) 18 / 54 4) 10 / 17

22/30 = 11/15
7/9 = 14/18
18/54 = 1/3
10/17 = 20/34

A proportion can be set up by using the general formula:
a/b = c/d
ad = bc

ANSWERED AT 16/02/2020 - 04:10 PM


QUESTION POSTED AT 16/02/2020 - 04:10 PM

Write the equation of the circle with center (-11, 3) and radius r = 9. Use the ^ key for the exponents. Write your answer as the example: (x - 4)^2+(y+8)^2=25

The equation of a circle with center (a, b) and radius = r is given by (x - a)^2 + (x - b)^2 = r^2
If center is (-11, 3) and radius is 9, then equation is
(x - (-11))^2 + (y - 3)^2 = 9^2
(x + 11)^2 + (y - 3)^2 = 81

ANSWERED AT 16/02/2020 - 04:09 PM


QUESTION POSTED AT 16/02/2020 - 04:09 PM

Two similar prisms have heights 4 cm and 10 cm. What is the ratio of their surface areas? A) 2:5 B) 4:25 C) 4:10 D) 8:125

H 1 : H 2 = 4 : 10
H 1 = 2/5 H 2
and also for the base: L 1 = 2/5 L 2 and W 1 = 2/5 L 2
 A 1 = 2 L 1 x W 1 + 2 L 1 x H 1 + 2 W 1 x H 1
A 2 = 2 L 2 x W 2 + 2 L 2 x H 2 + 2 W 2 x H 2
A 1 / A 2 = 4/25 *( 2 L 2 x W 2 + 2 L 2 x H 2 + 2 W 2 H 2 ) /
                 / ( 2 L 2 x W 2 + 2 L 2 x H 2 + 2 W 2 x H  2 ) =
= 4/5
A 1 : A 2 = 4 : 25
Answer:  B ) 4 : 25

ANSWERED AT 16/02/2020 - 04:08 PM


QUESTION POSTED AT 16/02/2020 - 04:08 PM

A ferris wheel is 35 meters in diameter and boarded at ground level. The wheel makes one full rotation every 8 minutes, and at time t = 0 you are at the 9 o'clock position and descending. Let f(t) denote your height (in meters) above ground at t minutes. Find a formula for f(t).

F(t) = -17.5sin((t/4)*pi) + 17.5
Because the ferris wheel is a circle you can use sine and cosine. As we are descending and in the middle of the descent the use of negative sine makes the most sense.
Period = 2pi.
Our period is 8 minutes.
8 minutes*w = 2pi
w = (t/4) * pi.
The 17.5 at the end is to take into account that we are 17.5 meteres up in the air at the start.

ANSWERED AT 16/02/2020 - 04:07 PM


QUESTION POSTED AT 16/02/2020 - 04:07 PM

The function h(d) = 2d+4.3 relates the h height of the water in a fountain in feet to the d diameter of the pipe carrying the water. Graph the function on a calculator and use the graph to find the height of the water when the pipe has a diameter of 1.5 inches

You can do what the directions say and enter the function into a calculator. if you're having trouble learning how to graph on a calculator, i would suggest looking up a tutorial with pictures or videos, since it would be really confusing to explain through text alone on this site.

however, you can solve it without use of a calculator; just plug in 1.5 inches for d.

h = 2(1.5) + 4.3
h = 7.3

the height is 7.3 when the diameter is 1.5

the way you should find this on a graph entered into a calculator would be by "tracing" the graph ("trace" should be a button on your calc). it prompts you to pick like a left/right bound, if i remember correctly, and it'll guess the point in the middle of them. if a graphing tutorial isn't helpful, you can always refer to the table function as well and change the settings so that it lets you enter your own x-values (yet another thing you can find how to do in the instruction booklet that came with your calc, or a visual tutorial). sorry i couldn't be more helpful in regards to the actual graphing! it's just a pretty confusing process to explain unless you can physically show the person with a calc of your own

ANSWERED AT 16/02/2020 - 04:02 PM


QUESTION POSTED AT 16/02/2020 - 04:02 PM

Steven cuts a 25-foot board into 2 pieces. One piece is 4 feet more than 2 times the length of the second piece. What is the length of the second, shorter, piece of the board?

Answer:

The length of the shorter piece of the board is 7 ft.

Step-by-step explanation:

Given,

The 25-foot board into 2 pieces.

Let x be the length of one piece,

So, the length of the other piece = ( 25 - x ) feet,

Now, according to the question,

25 - x = 2x + 4

-x - 2x = 4 - 25

-3x = - 21

x = 7

Hence, the length of two pieces are 7 feet and 18 feet,

In which 7 feet is the length of shorter piece.

ANSWERED AT 16/02/2020 - 04:02 PM


QUESTION POSTED AT 16/02/2020 - 04:02 PM

15 over 8 as a mixed number

1 and 7/8 bc 8 goes into 15 1 time and after you subtract 8 from 15 u get 7 and the remainder u just put over the original denominator

ANSWERED AT 16/02/2020 - 03:48 PM


QUESTION POSTED AT 16/02/2020 - 03:48 PM

If 45 is 15% of a value, what is that value?

45/.15

is 300

to check that, 300*15%= 45

so 45 is 15% of 300 :)

ANSWERED AT 16/02/2020 - 03:43 PM


QUESTION POSTED AT 16/02/2020 - 03:43 PM

A mountain climber is at an elevation of 10,712 feet. After 4 hours, he is at an elevation of 8,884 feet. Find the climber’s vertical speed using this formula:

I am not sure about the formula but if you subtract 8,884 from 10,712 you get 1,828. Then, if you divide that by 4 you get 457. 457 fph(feet per hour) should be the climbers vertical speed.

ANSWERED AT 16/02/2020 - 03:09 PM


QUESTION POSTED AT 16/02/2020 - 03:09 PM

A salesperson earning a 22.5% commission takes home $1,200 as a commission what was the dollar value of the items she sold

The equation is 1200/22.5 so 22.5% of 1200 is 53.33

ANSWERED AT 16/02/2020 - 06:13 AM


QUESTION POSTED AT 16/02/2020 - 06:13 AM