Jim Tree borrowed $1,000 at 10 percent for one year. He paid a $45 processing fee and $100 in interest. He calculated the APR to the nearest tenth.

145 / 1 000 = 0.145 = 15%

To calculate the APR (Annual Percentage Rate) to the nearest tenth, you need to use the formula:

APR = (Total Interest Paid / Principal Amount Borrowed) * 100

Given that Jim Tree borrowed $1,000 at 10 percent for one year, and he paid $100 in interest, the Total Interest Paid is $100.

Now, we need to find the Principal Amount Borrowed. Since Jim paid a processing fee of $45, which is not considered interest, we need to subtract it from the amount he borrowed.

Principal Amount Borrowed = Borrowed amount - Processing fee
= $1,000 - $45
= $955

Now, we can substitute the values into the formula to calculate the APR:

APR = (Total Interest Paid / Principal Amount Borrowed) * 100
= ($100 / $955) * 100
= 10.47

Therefore, to the nearest tenth, the APR is 10.5 percent.