Question

A spherical hot air balloon has a diameter of 55 feet when the balloon is inflated the radius increases at a rate of 1.5 feet per minute. approximately how long will it take to inflate a balloon 2/3 of its maximum volume? use. 3.14 as pie
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Answer 1

Answer: 46.90mins

Step-by-step explanation:

The given data:

The diameter of the balloon = 55 feet

The rate of increase of the radius of the balloon when inflated = 1.5 feet/min.

Solution:

dr/dt = 1.5 feet per minute = 1.5 ft/min

V = 4/3·π·r³

The maximum volume of the balloon

= 4/3 × 3.14 × 55³

= 696556.67 ft³

When the volume 2/3 the maximum volume

= 2/3 × 696556.67 ft³

= 464371.11 ft³

The radius, r₂ at the point is

= 4/3·π·r₂³

= 464371.11 ft³

r₂³ = 464371.11 ft³ × 3/4

= 348278.33 ft³

348278.333333

r₂ = ∛(348278.33 ft³) ≈ 70.36 ft

The time for the radius to increase to the above length = Length/(Rate of increase of length of the radius)

The time for the radius to increase to the

above length

Time taken for the radius to increase the length.

= is 70.369 ft/(1.5 ft/min)

= 46.90 minutes

46.90mins is the time taken to inflate the balloon.