The figure he came up with was really just a shot in the dark.

他得出的数字实际上只是瞎猜而已。

《牛津词典》

In one shot, standing on a runway in the dark, Chávez points to a building where he was imprisoned during a coup and where some of his men lost their lives.

在一个镜头中，查韦斯站在黑暗中的跑道上，指着一座他在一次政变中被囚禁的建筑，他的一些手下在那里丧生。

youdao

We had nothing to go by. It was a shot in the dark, but it turned out right.

我们是没有根据的，只不过瞎猜，可是结果却猜对了。

《新英汉大辞典》

Driven by a growing mound of student debt, the 18-year-old sports media major said his shot in the dark was low risk.

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Epstein tapped Freeman, who gathered John Lennon, Paul McCartney, George Harrison and Ringo Starr in a hotel dining room and shot a grainy, understated, black-and-white image of the four in dark turtlenecks -- the soon-to-be iconic "With the Beatles" cover.

CNN: Framing the Fab Four

These are all issues on which a vote for Mr Romney is more of a shot in the dark than a vote to re-elect the president.

ECONOMIST: Conclusion