A student eamed scores of 85, 83, 90, 94, 88, and 84 on the first six tests in a biology class. What score is needed on the seventh test to produce an 86 average?
To find the score needed on the seventh test to produce an 86 average, we need to calculate the total sum of the scores on the first six tests.
Sum of the scores on the first six tests = 85 + 83 + 90 + 94 + 88 + 84 = 524.
Now, let's assume that the score on the seventh test is x. The average of the seven tests can be calculated using the formula:
Average = (Sum of scores)/Number of scores
Since we want an average of 86, we can set up the equation:
86 = (524 + x)/7
Now, we can solve this equation for x:
86 * 7 = 524 + x
602 = 524 + x
602 - 524 = x
78 = x
Therefore, a score of 78 is needed on the seventh test to produce an 86 average.