'Thirty' in the Bible

When Adam had lived one hundred and thirty years, he became the father of a son in his own likeness, according to his image, and named him Seth.

So all the days that Adam lived were nine hundred and thirty years, and he died.

Then Mahalalel lived eight hundred and thirty years after he became the father of Jared, and he had other sons and daughters.

This is how you shall make it: the length of the ark three hundred cubits, its breadth fifty cubits, and its height thirty cubits.

Shelah lived thirty years, and became the father of Eber;

and Eber lived four hundred and thirty years after he became the father of Peleg, and he had other sons and daughters.

Peleg lived thirty years, and became the father of Reu;

Serug lived thirty years, and became the father of Nahor;

Then he said, “Oh may the Lord not be angry, and I shall speak; suppose thirty are found there?” And He said, “I will not do it if I find thirty there.”

thirty milking camels and their colts, forty cows and ten bulls, twenty female donkeys and ten male donkeys.

Now Joseph was thirty years old when he stood before Pharaoh, king of Egypt. And Joseph went out from the presence of Pharaoh and went through all the land of Egypt.

So Jacob said to Pharaoh, “The years of my sojourning are one hundred and thirty; few and unpleasant have been the years of my life, nor have they attained the years that my fathers lived during the days of their sojourning.”