Jerry went to a shop and bought things worth Rs. 30, out of which 30 % went on sales tax on taxable purchases. If the tax rate was 6%, then what was the cost of the tax free items?  Choose the correct choice from the following choices
A) 19  B) 19.7  C) 21.3  D) 21.5  E) 24.7

Rationale: "total cost of the items he purchased = rs . 30 given that out of this rs . 30 , 30 % is given as tax = > total tax incurred = 30 % = rs . 30 / 100 let the cost of the tax free items = x given that tax rate = 6 % ∴ ( 30 − 30 / 100 − x ) 6 / 100 = 30 / 100 ⇒ 6 ( 30 − 0.3 − x ) = 30 ⇒ ( 30 − 0.3 − x ) = 5 ⇒ x = 30 − 0.3 − 5 = 24.7 e )"
Answer: E