Step 1 :Convert the mixed number 6 3/4 to a decimal. This is done by adding the whole number 6 to the fraction 3/4, which gives 6.75.
Step 2 :Convert the decimal to a percent by multiplying by 100. This gives 675.
Step 3 :So, the mixed number 6 3/4 as a percent is \( \boxed{675\%} \).