Reginald answered 78% if the question correctly. what fractional part did he not answer correctly

We are given that Reginald answered = 78% questions.

Total questions in percentage form could be written as 100%.

Reginald answered = 78% so, Reginald answered didn't answer = 100-78 = 12%.

Now, we need to convert 12% into a fraction.

We know, a percentage represents out of 100. So, we need write 100 in the bottom of that number.

Therefore, 12% could be written as 12/100.

Now, we could reduce 12/100 into simplest fraction, by dividing by a common number in top and bottom.

12 and 100 both can be divided by 4.

Dividing 12 and 100  by 4, we get

Therefore, 3/25 fractional part did he not answer correctly.