Did zeros exist during vedic age?

A frustrated student asked his Maths teacher..

If Zero was invented by Aryabhatt and he was born in the Kalayuga... Then...

In the past in Satayuga, who counted 100 Kavravas and Ravana's 10 heads and How?😳😳🙄🙄🤔🤔🤔🤔

Teacher resigned and went back to Vedic education but is still not able to find the answer...

Joke apart but the point needs to noted...

P.s: Got the above msg as joke. But any reply for that?

An expert's answer is as follows:
Let me start with just 1 reference from Vedas and 1 from Puranas (to keep this answer short - we will not have enough space if we want to document all such references).

Vedic Reference (Yajur veda):
The Rishi Medhātithi, after preparing bricks for a Vedic ritual, prays to the Lord of fire, Agni.

Imā me Agna istakā dhenava Santvekā ća desa ća satam ća
Sahasram ćāyutam ća niyutam ća Prayutam ćārbudam ća nyarbudam ća
Samudrasća madhyam ćāntasća Parārdhasćaita me agna ishtakā
Dhenavasantvamutrāmushmimlloke .

(The mantra recited is in vogue for srivaikhanasa Archakas in Agniprathishta till now.... Ima me agna ishtaka....)

Meaning:
Oh Agni! Let these bricks be milk giving cows to me. Please give me one and ten and hundred and thousand. Ten thousand and lakh and ten lakh and One crore and ten crore and hundred crore, A thousand crore and one lakh crore in this world and other worlds too.

For starters, here is the meaning of some of the key words in that sloka:
eka - 1 (10 to the power 0)
dasa - 10 (10 to the power 1)
satam - 100 (10 square)
sahasram - 1000 (10 cube)
ayutam - 10000 (10 to the power 4)
niyutam - 100000 (10 to the power 5)
prayutam - 1000000 (10 to the power 6)
arbudam - 10000000 (10 to the power 7)
nyarbudam -100000000 (10 to the power 8)
samudram - 1000000000 (10 to the power 9)
madhyam - 1000000000 (10 to the poewr 10)
antam - 100000000000 (10 to the power 11)
parardham -1000000000000 (Trillion - 10 to the power 12)

Reference from Bhagavata Purana:
Chapter 3.11 of Srimad Bhagavatam explains the concept of time. It starts from what is now called nano seconds and goes up to trillions of years.

I have just given couple of references (which is just the tip of iceberg). If we read with an open mind we can find many more such references. This clearly shows that ancient Indians knew a lot of mathematics, counting, decimal systems etc. Why are we getting such "Intelligent" questions, when the truth is actually the opposite?

This question arises due to our ignorance. One of the biggest atrocity done by Britishers to India was to eradicate the Guru-Sishya tradition of educating our ancient knowledge and values. We are repeatedly fed irrelevant data about our past, to the extent that we all either feel ashamed to talk about it. Even those who talk, do so with a sense of guilt.
We also blindly vomit (reproduce) the Macaulay based education system that Britishers left us with. One of such nonsense is that Aryabhatta "invented" zero. This is an ambiguous statement, which doesn't give the right perspective to Aryabhatta's contribution. Another such nonsense is that there is Classical Sanskrit (whose grammar was codified by Panini) and then there is Vedic Sanskrit, which is somehow a different language. Absolutely wrong - Panini composed a treatise summarizing the Sanskrit grammar from days of yore - till his time. This doesn't mean that the language itself didn't exist or it existed as a different language.
We also have a distorted version of "Secularism" and it has become a fad among our generation to post such questions and jokes, which makes us look "cool".

Summary:
Rather than saying that Aryabhatta "Invented zero", I would say that he was the first person to formally define the place value system using Zero. He also elaborated on its mathematical usage. The alternative available was Roman numerals, which is not scalable (to the levels that our Vedas went). Why we refer Aryabhatta and not our Vedic and Puranic texts: Aryabhatta's work was intended to be a Mathematical treatise. His work summarizes the knowledge that was available with us until that time. Our Puranas and Itihasas on other hand, though had several references to larger and smaller numbers, were not Mathematical texts - Maths in them were incidental.