This is your answer and for the multiplication I gave it to you step by step
6 + 9x.....a common factor in both terms is 3
3(2 + 3x) <==
18,38,38,40,44,44,44,46,48....
the mean with the outlier (18) included is : 360/9 = 40
38,38,40,44,44,44,46,48
the mean with the outlier (18) excluded is : (360 - 18) / 9 = 342/9 = 38
so when the outlier is removed, the mean is 2 points less
Given:
15% of its height each day
27 inches on day 10.
How tall was it yesterday?
27 represents 115% of the height yesterday. So we divided 27 by 115% to get yesterdays height.
27 ÷ 115% = 23.48 inches.
The plant was 23.48 inches tall yesterday.
To check:
23.48 x 15% = 3.52 inches
23.48 + 3.52 = 27 inches