Well, the Hijri date 27 Jumada Al Oula 1399 corresponds to the Gregorian date Tuesday, 24 April 1979. This date lies in the fifth month of the Hijri year 1399 AH, which is Jumada Al-Awwal of 1399 AH. Both this Hijri and Gregorian date occur on the single day that is Tuesday without any doubt. The Arabic date 1399/05/27 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 24 April 1979 to its equivalent Arabic date.
The following is the conversion of the Arabic date 27 Jumada Al Oula 1399 AH to its equivalent Gregorian date.
وَيَجْعَلُونَ لِلَّهِ مَا يَكْرَهُونَ وَتَصِفُ أَلْسِنَتُهُمُ ٱلْكَذِبَ أَنَّ لَهُمُ ٱلْحُسْنَىٰ ۖ لَا جَرَمَ أَنَّ لَهُمُ ٱلنَّارَ وَأَنَّهُم مُّفْرَطُونَ
And they assign unto Allah that which they (themselves) dislike, and their tongues expound the lie that the better portion will be theirs. Assuredly theirs will be the Fire, and they will be abandoned.
Surah An-Nahl(16:62)