An employment agency requires applicants average at least 70% on a battery of four job skills tests. If an applicant scored 70%, 78%, and 82% on the first three exams, what must he score on the fourth test to maintain a 70% or better average?
4 * 70% = 280
70 + 78 + 82 = 230
280 - 230 = 50
To find the score the applicant must achieve on the fourth test to maintain a 70% or better average, we need to calculate the average of the four test scores.
Let's call the score on the fourth test "x".
The average of the four test scores will be (70% + 78% + 82% + x) / 4.
To maintain a 70% or better average, the applicant's average score should be at least 70%.
So, we can set up the equation:
(70% + 78% + 82% + x) / 4 ≥ 70%
Now, let's solve the equation step by step:
1. Combine the percentages: 70% + 78% + 82% = 230%.
2. Substitute the combined percentage into the equation: (230% + x) / 4 ≥ 70%.
3. Multiply both sides of the equation by 4 to eliminate the fraction: 230% + x ≥ 280%.
4. Subtract 230% from both sides of the equation: x ≥ 280% - 230%.
5. Simplify the right side of the equation: x ≥ 50%.
Therefore, the applicant must score 50% or higher on the fourth test to maintain a 70% or better average.
To determine the score the applicant needs on the fourth test to maintain a 70% or better average, we can use the following formula:
Total average = (Sum of scores) / (Number of tests)
Let's solve the problem step by step:
1. Add up the first three scores:
70 + 78 + 82 = 230
2. To maintain a 70% or better average, the total score after all four tests should be at least:
70% * 4 = 280
3. Now, subtract the sum of the first three scores from the required total score:
280 - 230 = 50
4. Therefore, the applicant must score at least 50% on the fourth test to maintain a 70% or better average.
Keep in mind that this approach assumes all tests have equal weight or importance. If each test has a different weight, you would need that information and adjust the calculations accordingly.