There are 600 students including the seventh and eighth graders at the party.
This problem uses the concept of percentages to define the conditions that are laid in front of us.
Let the original number of students be S , and the number of seventh graders be = 0.60S
We know that percent is used to convey the mathematical term of a fraction multiplied by 100.
Total students after 20 eighth graders arrive = S + 20
And we have that
Number of seventh graders / total number of students = 58%
.60S / [ S + 20 ] = .58 we multiply both sides by S + 20
0.60S =0 .58 [ S + 20]
.60S = .58S + 11.6 we subtract 0.58S from both the sides
0.02S = 11.6 we divide both the sides by .02
S = 11/6 / 0.02 = 580
So the total number of students = 580 + 20 = 600 .
Hence there are 600 students at the party at that time.
To learn more about students visit:
brainly.com/question/17332524
#SPJ1
Answer:
54 cents
Step-by-step explanation:
The cost of bookmarks relating to the number of bookmarks is given by the graph shown. Therefore:
From the graph, we can determine the relationship between the cost of bookmarks and the number of bookmarks by using two points. The equation of a line passing through points
is:

From the graph, y represents the cost of bookmarks in cents and x represent the number of bookmarks. we can see that it passes through the point (2, 30) and (7, 90). Hence:

The cost of 4 bookmarks (x = 4):
y = 12(4) + 6
y = 54 cents
<em>Complete Question:</em>
<em>You plant an 8-inch spruce tree that grows 4 inches per year and a 14-inch hemlock tree that grows 6 inches per year. </em>
<em>The initial heights are shown. </em>
Write a system of linear equations that represents this situation.
Answer:


Step-by-step explanation:
Given
Spruce Tree (s):

(yearly)
Hemlock Tree (h):

(yearly)
Required
Represent as system of linear equations
Let the number of years be x.
In both cases, the equation can be formed using:

For Spruce Tree (s):


For Hemlock Tree (h):


<em>Hence, the equations are </em>
<em> and </em>
<em></em>