Answer:
The volume of helium needed to fill 11 balloons is 19.4 ft³
C is correct
Explanation:
For a birthday party, Mrs. Guilliano bought 11 spherical balloons, each with an inflated diameter of 1.5 ft.
Balloons are spherical with diameter 1.5 ft
Radius of spherical = Half of diameter
Radius (r) = 0.75 ft
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Volume of each balloon
ft³
Amount of helium for 1 balloon = 1.767 ft³
Amount of helium for 11 balloons = 11 x 1.767 = 19.4 ft³
Hence, The volume of helium needed to fill 11 balloons is 19.4 ft³