84% of 50 is 42. So if your test was graded out of 50 you would've gotten 42/50. If you multiply 50 by 2 (50x2), you have 100, so then you'd just divide the 84% by 2 so you'd get 42%
To find the mean (average), we first need to add up all the test scores (14 + 19 + 19 + 20 + 16 + 18 + 15 + 17 + 12 = 150). Then, we need to divide that number (150) by the number of numbers in the data set (9 in this case). So the mean of these test scores is about 16.6666666667.
Answer:
90.00 increased by 20% is 108.00
The increase is 18.00
