answer.
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
Hitman42 [59]
1 year ago
12

8. Finley has 152 yellow, red, and blue marbles in a bag. He has seven more red marbles than yellow marbles, and three times as

many blue marbles as yellow marbles. How many yellow marbles does Finley have? Write an equation to represent this problem. Then solve the equation. A. x + x + 7 + 5x = 152; x = 21 B. x + x + 7 + 3x = 152; x = 29 C. x + x + 7 + x = 152; x = 48 D. x + x + 7 + 2x = 152; x = 36
Mathematics
1 answer:
DochEvi [55]1 year ago
5 0

Let number of yellow marbles = x

Let number of red marbles = y

Let number of blue marbles = z


Given that Finley has 152 yellow, red, and blue marbles in a bag.

So we get equation:

x+y+z=152...(i)


"He has seven more red marbles than yellow marbles" means:

y=x+7...(ii)

"three times as many blue marbles as yellow marbles." means:

z=3x...(iii)

Now we just need to solve those equations to find the answer.


Plug (ii) and (iii) into (i)


x+(x+7)+(3x)=152

x+x+7+3x=152

Which looks similar to choice (B)


5x+7=152

5x=145

x=29

Hence final answer is choice B.

Required equation is

x+x+7+3x=152

Number of yellow marbles = 29

You might be interested in
A piece of paper is to display ~128~ 128 space, 128, space square inches of text. If there are to be one-inch margins on both si
Grace [21]

Answer:

The dimensions of the smallest piece that can be used are: 10 by 20 and the area is 200 square inches

Step-by-step explanation:

We have that:

Area = 128

Let the dimension of the paper be x and y;

Such that:

Length = x

Width = y

So:

Area = x * y

Substitute 128 for Area

128 = x * y

Make x the subject

x = \frac{128}{y}

When 1 inch margin is at top and bottom

The length becomes:

Length = x + 1 + 1

Length = x + 2

When 2 inch margin is at both sides

The width becomes:

Width = y + 2 + 2

Width = y + 4

The New Area (A) is then calculated as:

A = (x + 2) * (y + 4)

Substitute \frac{128}{y} for x

A = (\frac{128}{y} + 2) * (y + 4)

Open Brackets

A = 128 + \frac{512}{y} + 2y + 8

Collect Like Terms

A = \frac{512}{y} + 2y + 8+128

A = \frac{512}{y} + 2y + 136

A= 512y^{-1} + 2y + 136

To calculate the smallest possible value of y, we have to apply calculus.

Different A with respect to y

A' = -512y^{-2} + 2

Set

A' = 0

This gives:

0 = -512y^{-2} + 2

Collect Like Terms

512y^{-2} = 2

Multiply through by y^2

y^2 * 512y^{-2} = 2 * y^2

512 = 2y^2

Divide through by 2

256=y^2

Take square roots of both sides

\sqrt{256=y^2

16=y

y = 16

Recall that:

x = \frac{128}{y}

x = \frac{128}{16}

x = 8

Recall that the new dimensions are:

Length = x + 2

Width = y + 4

So:

Length = 8 + 2

Length = 10

Width = 16 + 4

Width = 20

To double-check;

Differentiate A'

A' = -512y^{-2} + 2

A" = -2 * -512y^{-3}

A" = 1024y^{-3}

A" = \frac{1024}{y^3}

The above value is:

A" = \frac{1024}{y^3} > 0

This means that the calculated values are at minimum.

<em>Hence, the dimensions of the smallest piece that can be used are: 10 by 20 and the area is 200 square inches</em>

3 0
1 year ago
What do the differences between the points (as shown on the graph) represent?
Mekhanik [1.2K]

Answer:

They represent the rise and run of the graph.

Step-by-step explanation:

<em>The difference between the x-axis of the points represents the "run" of the graph (or how much you should run along x-axis to get to the next point.)</em>

<em>The difference between the y-axis of of the points represents the "rise" of the graph (or how much you should rise up the y-xis to get to the next point).</em>

The ratio of rise to run is the slope of the graph, which tells us  how many steps should we take on the y-axis for every step we move forward on the x-axis.

8 0
2 years ago
Read 2 more answers
A law school administrator was interested in whether a student's score on the entrance exam can be used to predict a student's g
frutty [35]

Answer:

The correlation coeffcient for this case was provided:

r =0.934

And this coefficient is very near to 1 the maximum possible value, so then we can interpret that the relationship between the entrace exam score and the grade point average are strongly linearly correlated .

We can also find the r^2 who represent the determination coefficient and we got:

r^2 = 0.934^2= 0.872

And the interpretation for this is that a linear model explains appproximately 87.2% of the variability between the two variables

Step-by-step explanation:

Previous concepts

The correlation coefficient is a "statistical measure that calculates the strength of the relationship between the relative movements of two variables". It's denoted by r and its always between -1 and 1.

And in order to calculate the correlation coefficient we can use this formula:  

r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}  

The correlation coeffcient for this case was provided:

r =0.934

And this coefficient is very near to 1 the maximum possible value, so then we can interpret that the relationship between the entrace exam score and the grade point average are strongly linearly correlated .

We can also find the r^2 who represent the determination coefficient and we got:

r^2 = 0.934^2= 0.872

And the interpretation for this is that a linear model explains appproximately 87.2% of the variability between the two variables

8 0
1 year ago
Without actually calculating the logarithm, determine what two integers the value of log(1.37×109) falls between.
jok3333 [9.3K]

 

First we need to find out what kind of logarithm rule is given, the given is logarithm product rule which states that a log of a product is equal to the sum of the log of the first base and the log of the second base.

By:

= log (1.37 x 10⁹) = log (1.37) + log (10⁹)

= log (1.37) + 9

= 9 + log (1.37)

In the meantime, 1.37 is between 1 and 10 its logarithm will be between 0 and 1. Thus, the value of log (1.37 x 10⁹) falls between 9 and 10 because when you compose a scientific notation you will always have a number among 1 and 10 by 10 to some power. That power tells you the integer part of the logarithm.

<span> </span>

6 0
2 years ago
Lawrence has two part-time jobs one at the movie theater and wanted a pet store he's paid by the hour at each job last week he w
alexandr402 [8]
Let x be the earnings/hour at the movie theater.
      y be the earnings/hour at the pet store

Systems of equations:

$152.50 = 10x + 8y
$171 = 8x + 10y

Solving for x and y:
x = $4.36/ hour in the movie theater
y = $13.61/ hour in the pet store.<span />
8 0
2 years ago
Other questions:
  • Sara drives 171 miles on 7.6 gallons of gas. She uses this information to calculate how many miles per gallon she can drive. Usi
    15·2 answers
  • Due to fire laws, no more than 720 people may attend a performance at metro auditorium. The balcony holds 120 people. There are
    7·1 answer
  • For three consecutive years, Sam invested some money at the start of the year. The first year, he invested x dollars. The second
    15·1 answer
  • An article reports Sales have grown by 30% this year to $200 million, what were sales before the growth?
    13·1 answer
  • In a survey of students, 80% were girls and 20% were boys. of the girls surveyed, 40% were wearing sneakers. if a surveyed stude
    11·1 answer
  • Evaluate the triple integral ∭Tx2dV, where T is the solid tetrahedron with vertices (0,0,0), (3,0,0), (0,3,0), and (0,0,3).
    7·1 answer
  • A polar vortex causes the temperature to decrease from 3 degrees Celsius at 3:00 P.M. to -2 degrees Celsius at 4:00 P.M. The tem
    15·1 answer
  • Ephemeral services corporation (esco) knows that nine other companies besides esco are bidding for a $900,000 government contrac
    7·1 answer
  • When 0.3(4x – 8) – 0.5(–2.4x + 4) is simplified, what is the resulting expression?
    7·1 answer
  • What is the slope of the line through (-9,6)(−9,6)left parenthesis, minus, 9, comma, 6, right parenthesis and (-6,-9)(−6,−9)left
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!