Is paying zakaat al-fitr obligatory for someone who only prayed on the last day of Ramadan and did not fast?
Question

                There is a person who did not pray or fast, but the last day of Ramadan Allah guided him, and he prayed and fasted. Does he have to pay zakaat al-fitr? If he did not pay it what should he do?.
Praise be to Allah.
    In the answer to question no.
    2182 we stated that the one who 
    does not pray is a kaafir, whether he does not pray out of carelessness and 
    laziness or because he denies it is obligatory. 

    If Allah guides a person (to Islam) before sunset on the last 
    day of Ramadan, he has to pay zakaat al-fitr, regardless of whether he 
    caught up with the fast or not, because of the hadeeth of Ibn ‘Umar (may 
    Allah be pleased with him) who said: The Messenger of Allah (blessings and 
    peace of Allah be upon him) enjoined the sadaqah of Ramadan upon the people, 
    a saa‘ of dates or a saa‘ of barley, upon every person, free or slave, male 
    or female, among the Muslims.

    Narrated by al-Bukhaari, 1503; Muslim, 984. 

    The words “among the Muslims” are general in meaning and 
    include everyone who became Muslim before sunset on the last day of Ramadan, 
    even if he did not fast. 

    Ibn Qudaamah (may Allah have mercy on him) said: … With 
    regard to the time when it becomes obligatory, it is when the Sun sets on 
    the last day of Ramadan. It becomes obligatory with the setting of the sun 
    on the last day of the month of Ramadan, so whoever becomes Muslim before 
    sunset has to pay zakaat al-fitr, but if he became Muslim after sunset, he 
    is not obliged to pay it. … al-Layth, Abu Thawr and ashaab al-ra’y said: It 
    becomes obligatory when dawn breaks on the day of Eid, and this was also 
    narrated from Maalik, because it is an act of worship that has to do with 
    Eid, so it does not become obligatory before the day of Eid.

    End quote from al-Mughni, 2/358 

    Al-Nawawi (may Allah have mercy on him) said: The correct 
    view in our opinion is that it becomes obligatory when the sun sets on the 
    night before Eid al-Fitr. This was the view of al-Thawri, Ahmad and Ishaaq, 
    and is mentioned in one report from Maalik. Abu Haneefah and his companions, 
    Abu Thawr, Dawood and another reported that Maalik said that it becomes 
    obligatory when dawn breaks.

    End quote from al-Majmoo‘, 6/88. See also Haashiyat 
    al-‘Adawi, 1/515 

    If he became Muslim after sunset on the last day of Ramadan, 
    then he does not have to pay zakaat al-fitr, because the month has ended, 
    except in the opinion of those who say that it becomes obligatory when dawn 
    breaks. The more correct view is that of the majority of scholars, because 
    of the words of Ibn ‘Umar (may Allah be pleased with him): The Messenger of 
    Allah (blessings and peace of Allah be upon him) enjoined zakaat al-fitr 
    after Ramadan. Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said: The 
    end of the fast of Ramadan comes when the sun sets on the night before Eid 
    al-Fitr.

    End quote from al-Sharh al-Mumti‘, 6/56.