Final answer:
Vero should score 94 on the next test to have an average mark of 85. Vero's median score is 82.
Step-by-step explanation:
To find the mark Vero should score on the next test, we can use the formula for the average: average = sum / number of elements. In this case, we have 3 test scores so far (82, 74, and 90) and we want the average to be 85.
To find the sum of the test scores, we add them together: 82 + 74 + 90 = 246.
Next, we can solve for the mark Vero should score on the next test: average = (246 + x) / 4, where x is the unknown test score. We can rearrange the equation to solve for x: 85 = (246 + x) / 4.
Multiplying both sides of the equation by 4, we get: 85 * 4 = 246 + x. Simplifying further, we have: 340 = 246 + x.
Finally, subtracting 246 from both sides, we find that x = 94. Therefore, Vero should score 94 on the next test to have an average mark of 85.
To find the median score, we need to arrange the test scores in ascending order. The three test scores are 82, 74, and 90.
Placing them in order, we get: 74, 82, 90. The median is the middle value, which in this case is 82. Therefore, Vero's median score is 82.