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
Subtract them left to right
He paid him : 24t + 15
for 3 hrs...
24(3) + 15 = 72 + 15 = $ 87
