If the Tories had given every non-Tory voter £50, it would've cost £70m less than the DUP deal

Details of the agreement between Prime Minister Theresa May's Conservative government and the Democratic Unionist Party (DUP) of Northern Ireland were revealed on Monday.

May and the DUP leader Arlene Foster shook hands on the deal which sees the DUP vow to support the Conservatives in key parliamentary votes in exchange for a "triple lock" on the state pension, the withdrawal of some Conservative manifesto pledges, and an extra £1 billion of funding for Northern Ireland, on top of the extra £500 million they usually receive.

Despite the government's protests to the contrary, it's being interpreted by much of the press that Theresa May has desperately bribed a Unionist party in Northern Ireland with investment, annoying Nationalists who claim it violates the Good Friday Agreement.

All to cling to power.

People are looking at the costs and the election results and working out whether this was really the cheapest way to buy a majority.

In the 2017 general election 18,566,218 votes were cast for parties other than the Conservatives. Bribing them all with £50 (assuming that's the going rate), costs you $928,310,900.

That's roughly £71.7 million short of the package pledged to Northern Ireland.

In other terms, the DUP just guaranteed an extra £3420.95 for Northern Ireland, per every vote they received in the election.

Or, as Theresa May needed only eight more seats for a majority, and was effectively 401 votes short in the eight closest Conservative losses - those 401 votes cost Theresa May roughly £2.5 million each.

More: There's no magic money tree - unless you're making a deal with the DUP