Which of these equations would be parallel to a line a slope of -7?

A school bought pens, each costing $1, and pencils, each costing $0.5. The cost of the whole purchase was $220. How many pens an

Mkey [24]

Answer:

120 pens and 200 pencils.

Explanation:

You can set a system of two equations.

1. Variables

x: number of pens
y: number of pencils

2. Cost

each pen costs $1, then x pens costs: x
each pencil costs $0.5, then y pencil costs: 0.5y

Then, the total cost is: x + 0.5y

The cost of the whole purchase was $ 220, then the first equation is:

x + 0.5y = 220 ↔ equation (1)

3. There were 80 more pencils than pens

Then:

pencils = 80 + pens

↓ ↓

y = 80 + x ↔ equation (2)

4. Solve the system

i) Substitute the equation (2) into the equation (1):

x + 0.5(80 + x) = 220

ii) Solve

x + 40 + 0.5x = 220

1.5x = 180

x = 180/1.5

x = 120 pens

iii) Substitute x = 120 into the equation (2)

y = 80 + 120

y = 200 pencils

Solution: 120 pens and 200 pencils ← answer

6 0

2 years ago

Which is greater five ones and eight tenths or fifty eight tenths

sergiy2304 [10]

They are equal. 0.1x58=5.8, 5+0.8=5.8

8 0

2 years ago

Read 2 more answers

Find the range and interquartile range of the data below. 13, 14, 15, 18, 19, 19, 19, 20

ELEN [110]

The answer to this problem is 7

7 0

3 years ago

A rectangle's length is 8 cm longer than

saul85 [17]

Answer:

The Answer is 96 .

Step-by-step explanation:

i hoped it's helpful

thank you ☺️☺️☺️

8 0

2 years ago

Please answer this with explanation. Please I really am struggling. I will mark you brainalist. Please solve it Please

Hatshy [7]

Answer:

13, 11, 4, 16, 6, 22

Step-by-step explanation:

Let the second digit be x and the last digit be y

Given:

Data set: 13, x, 4, 16, 6, y
Mean = 12
y = 2x or x = 2y

The mean of the data is the average. The average can be calculated by determining the sum of the terms and dividing it by the total digits.

$\implies \text{Mean of data:} \ \dfrac{13 + x + 4 + 16 + 6 + y}{6} = 12$

Let us substitute the value of y (2x) in the data.

$\implies \dfrac{13 + x + 4 + 16 + 6 + 2x}{6} = 12$

Now, add all the terms in the data and simplify.

$\implies \dfrac{39 + x +2x}{6} = 12$

$\implies \dfrac{39 + 3x}{6} = 12$

Distribute the denominators and simplify.

$\implies \dfrac{39}{6} + \dfrac{3x}{6} = 12$

$\implies \dfrac{13}{2} + \dfrac{x}{2} = 12$

$\implies 6.5 + \dfrac{x}{2} = 12$

Subtract 6.5 both sides and simplify.

$\implies 6.5 + \dfrac{x}{2} - 6.5 = 12 - 6.5$

$\implies \dfrac{x}{2} = 5.5$

Use cross multiplication and simplify.

$\implies x= 5.5 \times 2$

$\implies x= 11$

To determine the value of "y", simply substitute the value of "x" into the expression that represents the value of "y".

$\implies y = 2x$

$\implies y = 2(11)$

$\implies y = 22$

When the x and y values are substituted in the data, we get;

⇒ 13, 11, 4, 16, 6, 22

Therefore, the data is 13, 11, 4, 16, 6, 22.

8 0

1 year ago