Feliks saw the crest on the back of the envelope.

费利克斯看了看信封背面的顶饰。

youdao

The notes were always on scratch paper or the back of an envelope, nothing fancy.

这些笔记总是在便笺或信封背面上，没什么特别的。

《柯林斯英汉双解大词典》

The results of my informal, back-of-the-envelope calculations were rather disheartening.

根据我非正式的统计结果，我在信封背面所计算出的统计数值令人相当失望。

youdao

"Just a back-of-the-envelope calculation shows that in the Philippines, if we in a year can be reaching just five thousand farmers and their fields can be increasing the yield by half a ton per hectare, we could be looking at profitabilities for those farmers in the range of half a million dollars."

VOA: standard.2010.07.28

And then Citigroup analyst Oliver Chen did some back of the envelope calculations.

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And the second was just a back of the envelope opportunity analysis.

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Fifty years is, back of the envelope, 200 quarterly earnings reports.

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