Trish likes to go for walks every day. One day, she goes on a 1-mile walk. Every subsequent day, she doubles the distance she walked the previous day. On what day does she walk more than 10 times further than she did on the first day? Think carefully first, then make a decision:
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 = 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 = 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 = 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 = 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 miles,. Since she accomplished this on the 5th day of walking, the answer is 5. So, the answer is 5.