Chapter 6 Rational Exponents and Radical Functions - 6.2 Apply Properties of Rational Exponents - 6.2 Exercises - Problem Solving - Page 427: 89c

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From part b, we found: $S=(4\pi)^{1/3}(3V)^{2/3}$ Substitute $2V$ for $V$:$S=(4\pi)^{1/3}(3(2V))^{2/3}\\=(4\pi)^{1/3}(3V)^{2/3}(2)^{2/3}$ Since $2^{2/3}\approx1.587$, the surface areas of the two water balloons have about $1.587$ times as much surface area.