Answer:
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Step-by-step explanation:
we know that
The mean score is the total of all scores divided by the total number of tests.
Let
x_1 ----> the score in the first math test
x_2 ----> the score in the second math test
x_3 ----> the score in the third math test
x_4 ----> the score in the fourth math test
we have
After taking the first 3 tests, his mean test score is 88 points
so

----> equation A
How many points does he need on his last test to raise his mean test score to 90 points?
so

----> equation B
substitute equation A in equation B

solve for x_4


Therefore
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Im not sure about the given data but I plotted the scatter plot based on what I understand on how the data should be presented.
Time (years)
3, 6, 9, 12, 15, 18, 21, 24
Number of participants(x1000)
22, 25, 28, 14, 17, 20,15, 9
Attached is the scatter plot created online.
x = time (years)
y = number of participantep explanation
Answer:
2
Step-by-step explanation:
y would be the first number in the equation on the left side of the equal sign. This looks lik the y=mx+b formula, so m, being slope, would be 7, -3 would be x, and b would be 4.