ANSWER:

There are two types of rewards, one for praying with the imam and this is 27 times better than praying alone. The second type is praying with the congregation and this is greater in reward the bigger the congregation is. 

In your case, you won’t get the first reward unless being late was for a legitimate reason but will get the second one.

Sheikh,your answers for salah has helped me a lot. If I enter late in Masjid, and imam is in last tashahud, I join the imam in last tashahud, will reward of Jama ah(congregation) be given to me, I pray 4 after imam says salam.

Prayer | May 28, 2019 10:11 am
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Is it permissible to pray congregational prayers alone, isolated in the back/corner of the Masjid, because you have the flu (sore throat, coughing, runny nose, fever, etc.) to avoid passing it on to others?
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In India and Pakistan people say reading surah Iqlas thrice gives u a reward of reading d whole of Quran…so dey suggest u read surah Iqlas thrice in every rakath of any 1 salah of d day to gain d reward of reading d whole of Quran in dat particular salah again and again…so is it authentic and rogjt to follow or is it an innovation…