Re: On Monday, Jennifer placed 1 cent in her piggy bank. On Tuesday, she
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18 Jul 2022, 02:03
On Monday, Jennifer placed 1 cent in her piggy bank. On Tuesday, she put 2 cents in. On Wednesday, she added 4 cents, and on Thursday, she added 8 cents. If Jennifer continues this saving pattern, how much will be in her piggy bank after ten days?
ANSWER - $10.23
It’s possible to calculate each day’s addition to savings and then add, but it may be faster to look for a pattern in the cumulative sum. On day 1, she deposits 1 cents, for a total of 1 cents. On day 2, she deposits 2 cents for a total of 3 cents. On day 3, she deposits 4 cents for a total of 7 cents. Each day’s total is 1 cents less than the next day’s deposit. Calculate the deposit for the 11th day and subtract one to find the ten-day total. On the 11th day, she would deposit 210 cents, or $10.24, so the ten-day total is $10.23.