If you have an average score of x in five tests and you want to increase your average to y after taking one more test. What score do you need on that test?
If you have an average score of x in five tests and you want to increase your average to y after taking one more test. What score do you need on that test?
Explanation
Initial average score: x
Number of tests: 5
Total score so far: 5x
New average score desired: y
Total number of tests after one more: 6
Let's denote the score needed on the next test as 's'. The total score after 6 tests should be:
6y = 5x + s
Now, solve for 's':
s = 6y - 5x