You're correct, it is B. If you plug in 3 (weeks) in for "x" and 19 (amount saved) for "y" you will get 0=0, which is a solution.
The total number of students who studied only two subjects is 13.
The given parameters:
- <em>Total number of students, n = 55 </em>
- <em>Number of physics students = 21</em>
- <em>Number of geography students = 24</em>
- <em>Number of economics students = 23</em>
- <em>Number of students for the 3 subjects, = x</em>
- <em>Number of students who studied non = 2x</em>
The number of students who studied only two subjects can be determined by applying overlapping three sets formula as shown below;

Thus, the total number of students who studied only two subjects is 13.
Learn more about overlapping three sets here: brainly.com/question/2041029
Answer:
$8.65
Step-by-step explanation:
1.25+4.75+2.50=8.5
8.5+0.056(5.6%)=8.65