Question 816630: A clock chimes once after the first minute, again after 2 more minutes, again after 4 more minutes, again after 8 more minutes, again after 16 minutes, etc. My daughter is in 5th grade and the question is - How many times will the clock chime in 30 days?
What is the right approach, and please show the work so I can help her walk through it
Thank you
Answer by erica65404(394)   (Show Source):
You can put this solution on YOUR website! This is a rather extreme problem for a 5th grader, but i will do my best to help you out.
you want to start by making a sequence with maybe 5 or 6 numbers.
The sequence will correspond with the number of minutes at each chime
1, 3, 7, 15, 31, 63 ...
Now you want to find a rule. This really is a guess and check method.
For this sequence the equation is 
m is the number of minutes that have passed
n is the number of chimes.
Looking at the sequence 1, 3, 7, 15, 31, 63...
The first chime in the sequence n = 1
The second chime in the sequence n = 2
The third chime in the sequence n = 3
The fourth chime in the sequence n = 4
The fifth chime in the sequence n = 5
and so forth....
After the first minute, there is 1 chime. After 3 minutes, there are 2 chimes. After 7 minutes, there are 3 chimes.
Now to solve this equation. 30 days needs to be converted into minutes.
30 days equals 43,200 minutes. We are looking for n so we will use this equation.
Now you want to use logarithms on each side.
The bell will chime 15 times in 30 days.
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