In a turbulent sequence of events, Andersson had earlier in the day become the first woman elected to the post of prime minister in Sweden after clinching a last-minute deal with the Left party to raise pensions in exchange for its backing in Wednesdays vote.
But the small Centre party withdrew its support for Anderssons budget because of the concessions made to the Left, leaving the budget with insufficient votes to pass in parliament.
Parliament then adopted an alternative budget presented by the opposition conservative Moderates, Christian Democrats and far-right Sweden Democrats.
The fatal blow came when the Greens leader, Per Bolund, said his party could not tolerate the oppositions historic budget, drafted for the first time with the far right, and quit the government. Among other things, the Greens said a planned tax cut on petrol would lead to higher emissions.
https://www.theguardian.com/world/2021/nov/24/swedens-first-female-prime-minister-resigns-after-less-than-12-hours
Figures from Wikipedia - I hope these are correct:
349 total, so 175 is a majority:
Interim government (100):
Social Democrats (100)
Confidence and supply (75):
Centre Party (31)
Left Party (27)
Green Party (16)
Independent (1)
Opposition (174):
Moderate Party (70)
Sweden Democrats (62)
Christian Democrats (22)
Liberals (20)