c = circumference
pi = 3.14
r = radius = 9 inches
d = diameter
c=pi*d
The radius is half of the diameter, d = 2r. Then d = 2*9=18.
plug into equation. c= pi*d = 3.14*18
round accordingly and you may want to include that the measurement you end up with is in inches.
Me being a junior in high school and not knowing middle school math
Answer:
ur in rsm too? i have the same question sorry -_-
Step-by-step explanation:
The fact that it takes Earth 365 days to move year in and year out has been known for many centuries. Even before heliocentric and geocentric models were introduced, people were already familiar with the 365 day period. Perhaps Galileo would be the answer, but hasn't been truly defined as to who first observed this.