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
The total number of calories for 18 cups of milk is 1620 calories.
If two cups of milk is 180 calories then divide 180/2 to find the unit rate.
Then multiply 90 by the number of cups (18) and then you get the total number of calories for that many drinks.
