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
andrey2020 [161]
3 years ago
11

HELP :/ At the local pet store, Bloodfin Tetra cost $1.50 each and Angelfish cost $4.75 each. If Sarah bought 8 fish for a total

cost of $21.75, not including tax, how many of each type of fish did she buy?
Mathematics
1 answer:
kodGreya [7K]3 years ago
5 0

Answer:

Sarah bough 3 Angelfish and 5 Bloodfin Tetra

Step-by-step explanation:

Let a be the number of Angelfish fish and

b be the number of Bloodfin fish

Then according to the given statements

we get the following equations

a+b = 8\ \ \ Eqn\ 1\\4.75a+1.50b=21.75\ \ \ Eqn\ 2

From Equation 1

a = 8-b

Putting in equation 2

4.75(8-b)+1.50b = 21.75\\38-4.75b+1.50b = 21.75\\38-3.25b = 21.75\\-3.25b = 21.75-38\\-3.25b = -16.25\\\frac{-3.25b}{-3.25} = \frac{-16.25}{-3.25}\\b = 5

Putting b=5 in equation 1

a+5 = 8\\a = 8-5 = 3

Hence,

Sarah bough 3 Angelfish and 5 Bloodfin Tetra

You might be interested in
Helppppp someone answered the first half but I need the second half
Roman55 [17]

Answer:

i think its 182 dollars

Step-by-step explanation:

4 0
2 years ago
Read 2 more answers
You have a $10 balance in your checking account and you write a check for $12, what is your new balance?
lukranit [14]
-2 $
negative two is your answer
7 0
2 years ago
Read 2 more answers
A certain test preparation course is designed to help students improve their scores on the LSAT exam. A mock exam is given at th
Alborosie

Answer:

The 80% confidence interval for the average net change is (8.596, 12.904).

Critical value t=1.638.

Step-by-step explanation:

First, we calculate the mean and standard deviation of the sample:

M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{4}(12+7+13+11)\\\\\\M=\dfrac{43}{4}\\\\\\M=10.75\\\\\\s=\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2\\\\\\s=\dfrac{1}{3}((12-10.75)^2+(7-10.75)^2+(13-10.75)^2+(11-10.75)^2)\\\\\\s=\dfrac{20.75}{3}\\\\\\s=6.92\\\\\\

We have to calculate a 80% confidence interval for the mean.

The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.

The sample mean is M=10.75.

The sample size is N=4.

When σ is not known, s divided by the square root of N is used as an estimate of σM:

s_M=\dfrac{s}{\sqrt{N}}=\dfrac{2.63}{\sqrt{4}}=\dfrac{2.63}{2}=1.315

The degrees of freedom for this sample size are:

df=n-1=4-1=3

The t-value for a 80% confidence interval and 3 degrees of freedom is t=1.638.

The margin of error (MOE) can be calculated as:

MOE=t\cdot s_M=1.638 \cdot 1.315=2.154

Then, the lower and upper bounds of the confidence interval are:

LL=M-t \cdot s_M = 10.75-2.154=8.596\\\\UL=M+t \cdot s_M = 10.75+2.154=12.904

The 80% confidence interval for the average net change is (8.596, 12.904).

7 0
3 years ago
PLEASE HELP I NEED HELP ASAP PLEASEE
Serhud [2]
<h3>Answer: Choice C -- (0.6, 1.9)</h3>

Explanation:

Look through the table to see where f(x) and g(x) are the same value. Unfortunately this never happens for any row. However, we can get fairly close when we look at row two with f(x) = 1.8 and g(x) = 2; this input is x = 0.6

A good guess is that the midpoint of 1.8 and 2 is the y coordinate of the solution, so this is where the 1.9 comes from. You add 1.8 and 2 to get 3.8, then divide in half to get 1.9

So when x = 0.6 a good guess at the y value of the solution is y = 1.9, meaning that (0.6, 1.9) is an estimate of the solution

note: this is likely not the true solution, but it may be fairly close

5 0
3 years ago
Is the relation a function?<br> x2 + y2 = 16
nataly862011 [7]

Answer:

No.

Step-by-step explanation:

A function must pass the Vertical Line Test. The equation given is a circle on the coordinate plane. Therefore, since there will be 2 points for the same <em>x</em> value, it will not be a function.

6 0
3 years ago
Other questions:
  • HELP ASAP PLEASE I WILL GIVE YOU THE POINTS !!
    10·1 answer
  • Simplify.<br> -5x^4(-3x^2+4x-2)
    15·1 answer
  • Allison bought three pounds of strawberries for $19.20. What is the price, in dollars per ounce of strawberries?
    12·2 answers
  • The ratio of foreign students to American students at a college is 2 to 35. How many foreign students attend this college if the
    15·2 answers
  • Help me asap :) Giving Brainliest and rate!!
    14·2 answers
  • There are cars, trucks, and motorcycles in our company parking lot. The ratio of cars to trucks to motorcycles is $4:3:2.$ If th
    12·1 answer
  • Plzzzzzzzzz help meeeeeeeeee
    12·2 answers
  • What is 9 to the power of 4 + 6(7 x 3) - 3?
    12·1 answer
  • What is (3x+12)-(6x+5)
    5·1 answer
  • Use the substitution method
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!