Trish walks 1 mile on the first day, and since she walks double the previous day's amount each day that means she walks 1*2=<<1*2=2>>2 miles the second day.
On the following day, she walks double the distance of the previous day's total of 2 miles, meaning she walks 2*2=<<2*2=4>>4 miles that day.
On the following day, she walks double the distance of the previous day's total of 4 miles, meaning she walks 4*2=<<4*2=8>>8 miles that day.
On the following day, she walks double the distance of the previous day's total of 8 miles, meaning she walks 8*2=<<8*2=16>>16 miles that day.
As we're looking for the first day that her distance exceeds 10 times her original total, that means we're seeking a mile total of greater than or equal to 10*1= <<10*1=10>>10 miles,
Since she accomplished this on the 5th day of walking, the answer is <<5=5>>5.
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