Problema Solution
You collect marbles. Mary takes half of one less than the number of marbles you have. At the end you have 7. How many marbles did you start with?
Answer provided by our tutors
Let 'x' represent the number of marbles you start with.
x - (1/2)(x - 1) = 7
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click here to see the equation solved for x
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x = 13 marbles
You started with 13 marbles.