A theater has a seating capacity of 750 and charges $3 for children, s5 for students, and $7 for adults. At a certain screening with fll ttendance, there were combined. The receipts totaled $3450. How many children attended the show?

Answers

Answer 1
Answer:

Answer:

Between 150 and 450

Step-by-step explanation:

We are going to find the number by resolving  a system of linear equations.

First we write the system equations :

C+S+A=750

Where C : children, S : students and A : adults

The equation represents the ''full attendance''

The second equation :

3C+5S+7A=3450

This equation represents the totaled receipts.

The system :

C+S+A=750\n3C+5S+7A=3450

has the following associated matrix :

\left[\begin{array}{cccc}1&1&1&750\n3&5&7&3450\end{array}\right]

By performing elementary matrix operations we find that the matrix is equivalent to

\left[\begin{array}{cccc}1&0&-1&150\n0&1&2&600\n\end{array}\right]

The new system :

C-A=150\nS+2A=600

Working with the equations :

C = 150 + A\nS = 600-2A

Our solution vector is :

\left[\begin{array}{c}C&S&A\end{array}\right] =\left[\begin{array}{c}150+A&600-2A&A\end{array}\right]

For example :

If 0 adults attended ⇒ A = 0

C = 150 + 0 \nC = 150\nS = 600 - 2A\nS = 600

This verify the totaled receipts equation :

150($3)+600($5) = $ 3450

A ≥ 0 ⇒ If A = 0 ⇒ C = 150

C = 150 is the minimum children attendance

From the equation :

S = 600 -2A

S ≥0

600 - 2A ≥ 0

600 ≥ 2A

300≥ A

A is restricted to the interval [ 0, 300]

When A = 0 ⇒ C = 150

When A = 300 ⇒C = 150 + A = 150 + 300 = 450

Children ∈ [ 150,450]

With C being an integer number (including 0)

Also S and A are integer numbers (including 0)


Related Questions

Let X be the set of all 3×3 matrices whose diagonal entries are all 0. With the usual matrix addition and scalar multiplication, is X a vector space? (b) Let Y be the set of all 3 × 3 matrices whose diagonal entries add up to 0. With the usual matrix addition and scalar multiplication, is Y a vector space?
Which statement is true? Step by step.
What is the name of our number system?
Help I need this done
Two less than three-fourths of a number is, at most, negative seventeen. what is the range of values for the number?

What is the number if 2 is 12.5% of a number?
PLS HELP ME!!!

Answers

16 since 12.5% is 1/8 of 100 and 2 times 8 is 16

The answer to the question is 25.

Find the average speed. A= d\t
11) 360 miles in 6 hours​

Answers

Answer:

60 miles in a hour

Step-by-step explanation:

360 miles divided by 6 hours = 60 miles per hour

What is the solution to x+5>-7

Answers

According to the given data we have the following inequality:

x+5>-7

To find the solution of the inequality above we would make the following:

\begin{gathered} \mathrm{Subtract\: }5\mathrm{\: from\: both\: sides} \n x+5-5>-7-5 \end{gathered}\begin{gathered} \text{Finally, simplify},\text{ and so:} \n x>-12 \end{gathered}

Therefore, the solution to x+5>-7​ would be x>-12

A battery with 20 percent of its full capacity is connected to a charger. Every minute that passes, an additional 5% , percent of its capacity is charged.

Answers

Answer:

y = 5x + 20

Step-by-step explanation:

The initial percent is 20.

Every minute, the percent goes up 5%, so the slope is 5.

So the equation of the line is y = 5x + 20.

Ratio Question I Have the answer, just that I don't fully understand how you get it,
can someone go through the whole process for me?
Thanks.

Answers

Let "x" be the scaling factor
3x mums
2x dads

mums appt. + dads appt = total appointments
3x + 2x = 500

5x = 500
x = 100


300 appointments with mums
200 appointments with dads

Is the opposite of an opposite number always going to be positive?

Answers

No, the opposite of an opposite will not always be positive. the opposite of -4 is 4, and the opposite of that is -4, so the opposite of the opposite of the number -4 is -4, which is not positive. On the other hand, it CAN be positive. The opposite of 7 is -7, and opposite of that is 7, which is positive.
yes it is because if you reflect for a min, the opposite (which is a negative) of the opposite is always going to be a positive.