Answer: 7.5²π square centimeters. OR 56.25π cm²
Step-by-step explanation:
Circumference = diameter × π
So the diameter is 15 cm
Area = πr²
Radius is half the diameter, so 15/2 or 7.5
Area = (15/2)²π cm²
Answer:
126
Step-by-step explanation:
Total volume of sand = pi/3*(6^2)*(15) + pi*(6)^2*(30) = 1260*pi mm^3
So it will therefore take 1260*pi/10*pi = 126 seconds for all of the sand from the top hourglass to drip down to the bottom hourglass.
If Im correct I believe the answer is the last one