47. How old was Abraham when he left Haran?

75 years old

Abram [Abraham] was seventy and five years old when he departed out of Haran. Genesis 12:4

At least 135 years old

Abraham's father, Terah, was 70 years old when Abram was born.
And Terah lived seventy years, and begat Abram [Abraham]. Genesis 11:26-32
Abraham didn't leave Haran until after Terah died.
Our father Abraham ... dwelt in Haran: and from thence, when his father was dead, he removed himself into this land. Acts 7:2-4
And Terah lived to be 205. .
And the days of Terah were two hundred and five years; and Terah died in Haran. Genesis 11:32
So Abraham was at least 135 years old when he left Haran.

Christian Response
El Borak's Myopia