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
IgorC [24]
3 years ago
13

Sally is selling two types of seashells by the seashore. She is selling large and small shells. She sells small shells for 2 dol

lars each and large shells for 5 dollars each. She sold a combined 15 shells for total of 60 dollars. How many of each type of shell did she sell? Show your work.
A - 5 small shells and 10 large shells
B - 10 small shells and 5 large shells
C - 7 small shells and 8 large shells
D - 8 small shells and 7 large shells
Mathematics
1 answer:
Ostrovityanka [42]3 years ago
4 0

Answer:

The answer is A

Step-by-step explanation:

If you plug in the numbers it looks like this:

(A)  5(2) + 10(5) = 60

(B)  10(2) + 5(5) = 45

(C) 7(2) + 8(5) = 54

(D)  8(2) + 7(5)

so a is the only one that equals 60

You might be interested in
daniel is using a scale factor of 10 to enlarge a class photo that measures 3.5 inches by 5 inches what are The dimensions Love
Sholpan [36]
35 inches by 50 inches
6 0
2 years ago
What is the range of F(x)=72x-x^2
Marianna [84]

Answer:

Range of F(x) = (-∞ ,72).

Step-by-step explanation:

Range of the function F(x) means the set of values which are taken by the function along its domain.

F(x) = 72 - x^{2}

Since coefficient of x^{2} is negative on the right side ,

Maximum value of F(x) will come at x = 0.

Which is, F(0) = 72.

Now, as x increases , F(x) decreases , when x will reach infinity ,

F(x) will be reaching negative of infinity .

Thus, F(x) is ranging from -∞ to 72 .

Range of F(x) = (-∞ ,72).

3 0
2 years ago
Which is the equation of a parabola with a directrix at y = −3 and a focus at (5, 3)? y = one twelfth(x − 5^)2
ankoles [38]

The equation of a parabola with a directrix at y = -3 and a focus at (5 , 3) is y = one twelfth (x - 5)² ⇒ 1st answer

Step-by-step explanation:

The form of the equation of the parabola is  (x - h)² = 4p(y - k), where

  • The vertex of the parabola is (h , k)
  • The focus is (h , k + p)
  • The directrix is at y = k - p  

∵ The focus of the parabola is at (5 , 3)

- Compare it with the 2nd rule above

∴ h = 5

∴ k + p = 3 ⇒ (1)

∵ The directrix is at y = -3

- By using the 3rd rule above

∴ k - p = -3 ⇒ (2)

Solve the system of equations to find k and p

Add equations (1) and (2) to eliminate p

∴ 2k = 0

- Divide both sides by 2

∴ k = 0

- Substitute the value of k in equation (1) to find p

∵ 0 + p = 3

∴ p = 3

Substitute the values of h , k , and p in the form of the equation above

∵ (x - 5)² = 4(3)(y - 0)

∴ (x - 5)² = 12 y

- Divide both sides by 12

∴ \frac{1}{12} (x - 5)² = y

- Switch the two sides

∴ y =  \frac{1}{12} (x - 5)²

The equation of a parabola with a directrix at y = -3 and a focus at (5 , 3) is y =  \frac{1}{12} (x - 5)²

Learn more:

you can learn more about the quadratic equations in brainly.com/question/8054589

#LearnwithBrainly

8 0
3 years ago
Dylan Rieder is a statistics student investigating whether athletes have better balance than non-athletes for a thesis project.
Kobotan [32]

Answer:

t=\frac{(3.7-4.1)-0}{\sqrt{\frac{1.1^2}{32}+\frac{1.3^2}{45}}}}=-1.457

p_v =P(t_{75}  

Comparing the p value with a significance level for example \alpha=0.01 we see that p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can't say that the population mean for the athletes is significantly lower than the population mean for non athletes.  

Step-by-step explanation:

Data given and notation

\bar X_{A}=3.7 represent the mean for athletes  

\bar X_{NA}=4.1 represent the mean for non athletes  

s_{A}=1.1 represent the sample standard deviation for athletes  

s_{NA}=1.3 represent the sample standard deviation for non athletes

n_{A}=32 sample size for the group 2  

n_{NA}=45 sample size for the group 2  

\alpha=0.01 Significance level provided  

t would represent the statistic (variable of interest)  

Concepts and formulas to use  

We need to conduct a hypothesis in order to check if the population mean for athletes is lower than the population mean for non athletes, the system of  hypothesis would be:  

Null hypothesis:\mu_{A}-\mu_{NA}\geq 0  

Alternative hypothesis:\mu_{A} - \mu_{NA}< 0  

We don't have the population standard deviation's, we can apply a t test to compare means, and the statistic is given by:  

t=\frac{(\bar X_{A}-\bar X_{NA})-\Delta}{\sqrt{\frac{s^2_{A}}{n_{A}}+\frac{s^2_{NA}}{n_{NA}}}} (1)  

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.  

With the info given we can replace in formula (1) like this:  

t=\frac{(3.7-4.1)-0}{\sqrt{\frac{1.1^2}{32}+\frac{1.3^2}{45}}}}=-1.457

P value  

We need to find first the degrees of freedom given by:

df=n_A +n_{NA}-2=32+45-2=75

Since is a one left tailed test the p value would be:  

p_v =P(t_{75}  

Comparing the p value with a significance level for example \alpha=0.01 we see that p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can't say that the population mean for the athletes is significantly lower than the population mean for non athletes.  

5 0
3 years ago
Please guys help please
almond37 [142]
Wild guess a I’m only guessing
4 0
3 years ago
Other questions:
  • ( PLEASE ANSWER WILL GIVE BRAINIEST AND A THANK YOU ON PROFILE!!) On the previous problem, you found a unit rate of ounces per b
    8·2 answers
  • Which of the following is most likely to be a relative maximum for this graph?
    13·2 answers
  • 10 (w-4)=4 (w+4)+4w​
    15·1 answer
  • PLEASE HELP ME<br> Factor each expression,<br>  2n^(2)+ 3n -2
    12·1 answer
  • A cone is not a polyhedron. true or false?
    15·2 answers
  • How do I solve -2 = 12/x?​
    12·2 answers
  • I have no clue what this is, never learned it yet
    12·1 answer
  • Now that you know Theresa's height, find Paul's and Steve's height. Plug Theresa's height into the expressions for Paul's height
    8·1 answer
  • What is the slope between (2, 7) and (3, 3)
    13·1 answer
  • A projectile is fired straight upward from the Earth's surface with an initial speed of 33.3m/sec. What is it's speed after 2.8s
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!