The area enclosed by the circumferences of two concentric circles is $346.5\, cm^2$. If the circumference of the inner circle is $88$ cm, then the radius of the outer circle is

The area enclosed between the concentric circles is pi(R^2 - r^2) = 346.5, where R is the outer radius and r is the inner radius. The circumference of the inner circle is 88 cm, so 2 pi r = 88, which gives r = 14 cm. Substituting r into the area equation gives pi(R^2 - 14^2) = 346.5, simplifying to R^2 - 196 = 110.25. Solving for R gives R^2 = 306.25, so R = 17.5 cm. The result is 17.5 cm.

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