Answer:
There are 80 marks in total.
Step-by-step explanation:
Let the number of total marks be
.
The percentage score of the student can be written as the ratio
.
However,
.
Equating the two:
.
Cross-multiply (that is: multiple both sides by
, the product of the two denominators) to get
.
.
In other words, there are 80 marks in total.
When two quantities have a relationship, there is a corresponding equation that could describe it. These two quantities may be expressed in variables of x and y. When you plot the graph, you may see a line or a curve. This presents the trend of the relationship of the two quantities when the independent variable changes.
X+6=11
X-11=-6
5x=25
2x=10
2x+15=25
C = children
A = adults
293 = c + a
1.50c + 2.50a = 676.50
We can use substitution to solve:
c + a = 293 subtract a to get c = 293 - a
Plug this into the second equation:
1.50(293 - a) + 2.50a = 676.50
439.5 - 1.50a + 2.50a = 676.50
439.5 + 1a = 676.50
a = 237
Substitute this into the first equation:
293 = c + 237
56 = c