"serious solutions" is correct and commonly used in written English.
Example: The government needs to come up with some serious solutions to address the issue of rising unemployment.
Serious solutions share the costs equitably.
"There were no serious solutions to pressing problems.
We need serious discussion with serious people looking for serious solutions.
It's a mindset that gave us political talking points, not serious solutions.
Opponents have taken this to mean that the Labour leader simply lacks serious solutions.
We need leaders who offer serious solutions to secure our border and fix our broken immigration system".
If that sounds like a poll-tested P.R. gimmick rather than a serious solution, that's because it is.
Unless we seriously address these questions, I cannot see any significant change or serious solution to climate change.
"Over the last few days, your approach has been devoid of any serious solution to the crisis.
"This is not a serious solution for deficit control or getting this dismal economy on its feet," Mr. Brady said.
Any serious solution should focus exclusively on this problem – the collapse of investigative journalism, not the fate of particular delivery systems.
