Susan finished typing 1/9 of an article in the first houe and finished 1.4 of the remaining in the second hour. she then typed 2.3 of the leftover from the first two hours in the third hour.
left over from the first hour= 8/9
fraction of article typed on 2nd hour= 4/9???
leftover from the first two hours= 5/9??
fraction of article typed on 3rd hour=2/3????
fraction of the article typed in these 3 hours= ???
The fraction in the second hour...1/4 of 8/9 or 2/9 typed, or now 6/9 remaining.
fraction typed in third hour 2/3 of 6/9 or 4/9, so left over now is 6/9-4/9 or 2/9
To find the fraction of the article typed in these three hours, we need to add up all the fractions Susan typed.
In the first hour, Susan typed 1/9 of the article, which means 8/9 is left over.
In the second hour, Susan typed 1.4 times the remaining, which is 1.4 * 8/9 = 11.2/9. However, since we want the fraction, we need to convert 11.2/9 into a fraction. To do this, we can simplify the fraction by dividing both the numerator and denominator by their greatest common divisor, which is 1.2. So, 11.2/9 simplifies to 9/5. Therefore, Susan typed 9/5 of the remaining article in the second hour, leaving 8/9 - 9/5 = 23/45 remaining.
In the third hour, Susan typed 2.3 times the remaining from the first two hours, which is 2.3 * 23/45 = 52.9/45. Simplifying this fraction, we get 29/25. Hence, Susan typed 29/25 of the remaining article in the third hour, which leaves us with 23/45 - 29/25 = 218/225 remaining.
Now, to find the fraction of the article typed in these three hours, we subtract the remaining fraction from the whole article fraction (1/1). So, 1 - 218/225 = (225/225) - (218/225) = 7/225.
Therefore, the fraction of the article typed in these three hours is 7/225.