SOLUTION: Corey collected 4 pounds of newspaper on day 1. Each day after day 1, he collected 4 times the amount he had collected the previous day. On which day did he first collect over 1

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Question 852826:
Corey collected 4 pounds of newspaper on day 1. Each day after day 1, he collected 4 times the amount he had collected the previous day. On which day did he first collect over 1000 pounds of newspaper??
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
On day +n+, He collected +4%2A4%5E%28n-1%29+ pounds
+1000+=+4%2A4%5E%28n-1%29+
+4%5E%28n-1%29+=+250+
+4%5En+%2F+4++=+250+
+4%5En+=+1000+
+n%2Alog%284%29+=+log%28+1000+%29+
+n+=+3%2Flog%284%29+
+n+=+3%2F.6021+
+n+=+4.98+
On the 5th day he collected over 1,000 pounds
check:
+n+=+5+
+4%2A4%5E%285+-+1%29+
+4%2A4%5E4+
+4%5E5+=+1024+
OK