MathDB
Problems
Contests
National and Regional Contests
Canada Contests
Gauss
1998 Gauss
22
22
Part of
1998 Gauss
Problems
(1)
Gauss (7) #22
Source:
2/26/2017
Each time a bar of soap is used, its volume decreases by
10
%
10\%
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?
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5
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6
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<span class='latex-bold'>(A)</span>\ 5 \qquad <span class='latex-bold'>(B)</span>\ 6 \qquad <span class='latex-bold'>(C)</span>\ 7 \qquad <span class='latex-bold'>(D)</span>\ 8 \qquad <span class='latex-bold'>(E)</span>\ 9
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9
Gauss