If the original price of a garment is 200 yuan and the price is 242 yuan after two consecutive price increases of a%, the value of a is () A. 5B. 10C. 15D. 21
200 (1 + a%) 2 = 242, sorting out (1 + a%) 2 = 1.21, the solution is a% = 0.1 = 10% or a% = - 2.1 (rounding off)
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