Step 1:
The first step to converting 260.40780378905 to a fraction is to re-write 260.40780378905 in the form p/q where p and q are both positive integers. To start with, 260.40780378905 can be written as simply 260.40780378905/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 260.40780378905, which in this case is 11. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 260.40780378905/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 260.40780378905/1 each by 100000000000:
Step 3:
Now the last step is to simplify the fraction (if possible) by finding similar factors and cancelling them out, which leads to the following answer for 260.40780378905 as a fraction:
19791/76 / 1