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jmc

prealgebra junior

Problem

On Monday Taye has . Every day, he either gains or doubles the amount of money he had on the previous day. How many different dollar amounts could Taye have on Thursday, days later?
(A)
(B)
(C)
(D)
Solution
How many values could be on the first day? Only dollars. The second day, you can either add dollars, or double, so you can have dollars, or . For each of these values, you have values for each. For dollars, you have dollars or , and for dollars, you have dollars or $. Now, you have values for each of these. For dollars, you have dollars or , for dollars, you have dollars or , for dollars, you have dollars or , and for dollars, you have dollars or . On the final day, there are 11, 11, 16, and 16 repeating, leaving you with different values.
Final answer
D