All categories

2 years ago

Fuffy spent $7.20 on 4 dozen pencils. How much did each pencil cost

Mathematics

1 answer:

Valentin [98]2 years ago

3 0

Answer:

he spent $0.15 on each pencil

Step-by-step explanation:

12x4= 48, which is the exact amount of pencils he bought, and then divide them by the price

7.20 divided by 48 is 0.15.

Therefore, each pencil is 0.15 cents a piece

You might be interested in

A. Do some research and find a city that has experienced population growth.

horrorfan [7]

A. The city we will use is Orlando, Florida, and we are going to examine its population growth from 2000 to 2010. According to the census the population of Orlando was 192,157 in 2000 and 238,300 in 2010. To examine this population growth period, we will use the standard population growth equation $N_{t} =N _{0}e^{rt}$
where:
$N(t)$ is the population after $t$ years
$N_{0}$ is the initial population
$t$ is the time in years
$r$ is the growth rate in decimal form
$e$ is the Euler's constant
We now for our investigation that $N(t)=238300$ , $N_{0} =192157$ , and $t=10$ ; lets replace those values in our equation to find $r$ :
$238300=192157e^{10r}$
$e^{10r} = \frac{238300}{192157}$
$ln(e^{10r} )=ln( \frac{238300}{192157} )$
$r= \frac{ln( \frac{238300}{192157}) }{10}$
$r=0.022$
Now lets multiply $r$ by 100% to obtain our growth rate as a percentage:
$(0.022)(100)$ =2.2%
We just show that Orlando's population has been growing at a rate of 2.2% from 2000 to 2010. Its population increased from 192,157 to 238,300 in ten years.

B. Here we will examine the population decline of Detroit, Michigan over a period of ten years: 2000 to 2010.
Population in 2000: 951,307
Population in 2010: 713,777
We know from our investigation that $N(t)=713777$ , $N_{0} =951307$ , and $t=10$ . Just like before, lets replace those values into our equation to find $r$ :
$713777=951307e^{10r}$
$e^{10r} = \frac{713777}{951307}$
$ln(e^{10r} )=ln( \frac{713777}{951307} )$
$r= \frac{ln( \frac{713777}{951307}) }{10}$
$r=-0.029$
$(-0.029)(100)$ = -2.9%.
We just show that Detroit's population has been declining at a rate of 2.2% from 2000 to 2010. Its population increased from 192,157 to 238,300 in ten years.

C. Final equation from point A: $N(t)=192157e^{0.022t}$ .
Final equation from point B: $N(t)=951307e^{-0.029t}$
Similarities: Both have an initial population and use the same Euler's constant.
Differences: In the equation from point A the exponent is positive, which means that the function is growing; whereas, in equation from point B the exponent is negative, which means that the functions is decaying.

D. To find the year in which the population of Orlando will exceed the population of Detroit, we are going equate both equations $N(t)=192157e^{0.022t}$ and $N(t)=951307e^{-0.029t}$ and solve for t:
$192157e^{0.022t} =951307e^{-0.029t}$
$\frac{192157e^{0.022t} }{951307e^{-0.029t} } =1$
$e^{0.051t} = \frac{951307}{192157}$
$ln(e^{0.051t})=ln( \frac{951307}{192157})$
$t= \frac{ln( \frac{951307}{192157}) }{0.051}$
$t=31.36$
We can conclude that if Orlando's population keeps growing at the same rate and Detroit's keeps declining at the same rate, after 31.36 years in May of 2031 Orlando's population will surpass Detroit's population.

E. Since we know that the population of Detroit as 2000 is 951307, twice that population will be $2(951307)=1902614$ . Now we can rewrite our equation as: $N(t)=1902614e^{-0.029t}$ . The last thing we need to do is equate our Orlando's population growth equation with this new one and solve for t:
$192157e^{0.022t} =1902614e^{-0.029t}$
$\frac{192157e^{0.022t} }{1902614e^{-0.029t} } =1$
$e^{0.051t} = \frac{1902614}{192157}$
$ln(e^{0.051t} )=ln( \frac{1902614}{192157} )$
$t= \frac{ln( \frac{1902614}{192157}) }{0.051}$
$t=44.95$
We can conclude that after 45 years in 2045 the population of Orlando will exceed twice the population of Detroit.

8 0

3 years ago

Given points A(-3, 2), B(7, 8), and C(10,3) of parallelogram ABCD, find the coordinates of D that complete the parallelogram cor

dlinn [17]

I believe it is(0,-3)

6 0

3 years ago

What is one reason why we add and subtract decimals

NemiM [27]

Because if you did not you would not have a exact answer.

5 0

3 years ago

Read 2 more answers

Mr. Schaeffer worked the ticket booth at the football game last Friday night

Afina-wow [57]

And....?

There's not enough info for me to answer.

7 0

3 years ago

Paint can be purchased in two sizes: 1 gallon for $45.99 or 1 quart for $14.99.(round to the hundredths place)a.unit ratio of 1

ExtremeBDS [4]

Answer:

a. $0.47 per ounce

b. $0.36 per ounce

c. the gallon size costs less per ounce

Step-by-step explanation:

A unit rate is a rate that is expressed with one unit in the denominator. That is, it is <some amount> per unit. The <some amount> value will generally depend on what unit is chosen. This problem suggests the desired unit is 1 oz of paint.

Unit cost for a quart:

ratio = cost/ounces = $14.99/(32 oz) ≈ $0.468/oz ≈ $0.47/oz

Unit cost for a gallon:

ratio = cost/ounces = $45.99/(120 oz) ≈ $0.359/oz ≈ $0.36/oz

The cost per ounce is less for the gallon size. If at least 3 quarts of paint is needed, then buying it in the gallon size will cost less.

If less than 3 quarts are needed, then a gallon container will cost more than is necessary for the paint required. The "better deal" depends on the amount of paint required.

3 0

2 years ago