Question 335701: On average it takes 0.6 of a second to count a single digit number, 0.8 of a second to count a 2-digit number, 1.2 seconds to count a 3-digit number, 2.1 seconds to count a 4-digit number, 2.4 seconds to count a 5-digit number, 3.0 seconds to count a 6-digit number, and 0.8 of a second to count the number 1 million. If two friends take turns counting and sleeping so that no time is wasted, how long will it take them to count from one to one million?
I thought if I took the average of all the numbers 0.6+0.8+1.2+2.1+2.4+3.0+0.8=10.9 /7 1.55 or 2seconds per number
then there are 86,400 seconds in a day or (60*60*24) so I thought that 2,000,000/86400=23.1 days is that right???
Answer by solver91311(24713)   (Show Source):
You can put this solution on YOUR website!
Nope.
There are only 9 one-digit numbers (if you start from 1)
Then there are 90 two-digit numbers
Then there are 900 three digit numbers...
You should start seeing the pattern by now.
So you need 9 times 0.6 plus 90 times 0.8 plus 900 times 1.2, and so on. Finish up with 1 times 0.8. All that gets you the number of seconds which you need to divide by 86,400. The answer you gave was only about 2/3 of the correct answer. Write back and let me know what you got.
John
My calculator said it, I believe it, that settles it
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