A man has a million dollars. If he spends half of his money each day, how many days will it take for him to have less than a dollar left?
I know that the common ratio is 1/2, but I don't know how to set it up...
+129839 The amount that the man has left after n days is given by :
1,000,000(1/2)n
And we're looking for this
1,000,000(1/2)n = 1 divide both sides by 1,000,000
(1/2)n 1 / 1,000,000 taking the log of both sides
log (1/2)n log (1/1,000,000) and we can write
n = log(1/2) log (1 / 1,000,000) divide each side by log (1/2)
n = log (1/1,000,000) / log (1/2)
n = about 19.9 days
So....it will take him approximately 20 days to have < $1 left
+129839 The amount that the man has left after n days is given by :
1,000,000(1/2)n
And we're looking for this
1,000,000(1/2)n = 1 divide both sides by 1,000,000
(1/2)n 1 / 1,000,000 taking the log of both sides
log (1/2)n log (1/1,000,000) and we can write
n = log(1/2) log (1 / 1,000,000) divide each side by log (1/2)
n = log (1/1,000,000) / log (1/2)
n = about 19.9 days
So....it will take him approximately 20 days to have < $1 left
