First, find the mean. You'll need it to compute the variance.

The variance of the sample is then computed with the formula

The standard deviation is the square root of the variance, so
I think it’s like that but u shld wait for someone else to answer, cuz i’m not sure if im correct cuz the ans is so big
Answer:
Step-by-step explanation:
ax - b = 3x + 5d
For x;
ax = 3x + 5d +b
x = (3x + 5d + b)/a
Now for d;
ax - b -3x = 5d
d= (ax - b - 3x)/5
It is just 18 :)It is just 18 :)