Well,you have the answer on your paper already...
The height of the blue spruce was 45.
We find the mean by adding all of the data points and dividing by the number of data points. We will add the unknown value x and change the number we're dividing by to 7:
(160+320+100+110+200+220+x)/7 = 165
(1110+x)/7 = 165
Multiply both sides by 7:
1110 + x = 1155
Subtract 1110 from both sides:
x = 45
See attachment for math work and answer.
Answer:
34
Step-by-step explanation:
The mean is calculated as
mean = 
let x be the missing frequency, then
Total frequency × midpoint
= (16 × 2) + 7x + (20 × 12) + (10 × 17) = 32 + 7x + 240 + 170 = 442 + 7x
Total frequency = 16 + x + 20 + 10 = 46 + x, thus
= 8.5 ( cross- multiply )
442 + 7x = 8.5(46 + x)
442 + 7x = 391 + 8.5x ( subtract 8.5x from both sides )
442 - 1.5x = 391 ( subtract 442 from both sides )
- 1.5x = - 51 ( divide both sides by - 1.5 )
x = 34
The missing frequency is 34
I never took geometry but good luck and gh= 3