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CEMC Gauss (Grade 7), 1998

Algebra Difficulty 2.0 Junior Find the answer Canada

Each time a bar of soap is used, its volume decreases by 10%. What is the minimum number of times a new bar would have to be used so that less than one-half its volume remains?

(A) $5$ (B) $6$ (C) $7$ (D) $8$ (E) $9$

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