So when did mankind come into existence according to the quran

When Adam, peace be upon him, was created, I assume?

yes but the question is when?

The exact date isn't known (I don't think it is even mentioned in the Quran for that matter) but from what I remember from Islamic classes, there weren't any dinosaurs on the planet at the time, so it must have been post-jurassic era.

When Adam was brought to life, if you mean the time and date I don't know.

so it simply implies that dinosaurs were extinct before the mankind. It's just an implication though the quran never mentions it explicitly. well I do know that the age of the earth according to the quran is around 300000 years(sura 70:4). correct me if i'm wrong. when man was created you don;t really know for sure.

To someone else who asked me whether this discussion is relevant. Well as far as I am concerned. for me it is relevant. As I mentioned on my forst post. I want to know what you guys exactly believe on how and why you think. so that I can understand you better. it gives me every right to question any how I want to question and what I want to know from you. it is very diificult for me to look at your religous text objectively which is why i am seeking ur help.

So back to this discussion it's about dinosaurs, mankind and age of the earth?

Humankind came after dinasaurs became extinct.

You mistranslated verse 70:4 to get that conclusion - How has angels taking 50,000 years to get to him (as a day) equate to creation of universe being 50,000 x 6 days?

Some tafsir on that verse:

((Whereby) the angels and the Spirit) i.e. Gabriel (ascend unto Him) unto Allah (in a Day whereof the span) the span of ascending it for other than the angels (is fifty thousand years) it is also said that this means: it is from Allah that the punishment of the disbelievers comes in a day whose span is 50,000 years; and it is also said that this means: if anyone, other than Allah, were given the reckoning of people, such reckoning would not finish in 50,000 years. - Ibn Abbas

How embarrassing for you, not only do you not do any minor research before you write, but you seem to have ignored the post where I have quoted you that exact same verse.. Are you just looking to waste time? I so despise repeating myself or entertaining folly!
[Pickthal 70:4] (Whereby) the angels and the Spirit ascend unto Him in a Day whereof the span is fifty thousand years.

Actually it doesn't imply any of those things.
1. age of the earth is not given
2. when dinos became extint is not given.
3. when first human was created is not given.

50,000 years was a response to Quresh jesting about when would God send his wrath.

Subject mattar of this whole surah is as follows:

It admonishes and gives warning to the disbelievers who made fun of the news about Resurrection and the Hereafter, and Hell and Heaven, and challenged the Holy Prophet (upon whom be peace) to cause Resurrection with which he threatened them to take place if what he said was true and they had become worthy of the punishment in Hell by denying it. The whole Surah is meant to answer this denial.

The Surah opens with words to the effect:"A demander has demanded a torment, the torment which must befall the deniers; and when it takes place, there will be none to prevent it, but it will take place at its own appointed time. Allah has His own way of doing things, but He is not unjust. Therefore, have patience, O Prophet, at what they say. They think it is far off, but We see it as near at hand."

Then it is said:"Resurrection, which they desire to be hastened out of jest and fun, is terrible, and when it comes, it will cause great distress to the culprits. At that time they will even be prepared to give away their wives and children and their nearest kinsfolk in ransom to escape the punishment, but they will not be able to escape it.

Then the people have been warned to the effect; "On that Day the destinies of men will be decided strictly on the basis of their belief and their conduct. Those who turn away from the Truth in the world and amass wealth and withhold it from the needy, will be doomed to Hell; and those who fear the punishment of God here, believe in the Hereafter, keep up the Prayer, discharge the rights of the needy out of their wealth, strictly avoid immoral and wicked deeds, practise honesty in all their dealings, fulfill their pledges and trust and bear true witness, will have a place of honor in Paradise"

In conclusion, the disbelievers of Makkah who rushed in upon the Holy Prophet (upon whom be peace) from every side as soon as they saw him, in order to make fun of him, have been warned to the effect: "If you do not believe, Allah will replace you by other people who will be better than you", and the Holy Prophet (upon whom be peace) has been consoled, so as to say: "Do not take to heart their mockery and jesting; leave them to indulge in their idle talk and foolish conduct if they are bent upon experiencing the disgrace and humiliation of the Resurrection; they will themselves see their evil end."'

http://www.usc.edu/dept/MSA/quran/maududi/mau70.html

I knew myself that I was not so sure which is why I asked people to correct me if I was wrong.

John, how old do you think the Earth is?