shell paid 776 million for arrow stake?, page-20

Arrow started off with a total Queensland acreage worth A. Shell paid $776 million for 30% of A.

0.3 * A = $776 million
A = $776 million / 0.3 = $2587 million

So the original value of Arrow's acreage was $2587 million, but now they only have 70% of this left:

0.7 * $2587 million = $1811 million

As I said, Arrow is not just a junior gas explorer in Queensland and any takeover offer would have to reflect the value of the whole business, but the $1.8 billion valuation is a minimum based on the original Shell deal, and equates to about $2.50 a share.