一起学英语：这个速算小窍门不是人人都知道

有人问你85×85=？你能不到1秒钟回答他是7225吗？

Somebody asked you 85×85=? Can you give him 7225 in less than a second？

有人问你195×195=？你能不到2秒钟回答他是38025吗？

Somebody asked you 195×195=? Can you give him 38025 in less than 2 seconds？

后面带5的数字平方值，就等于前面的“数”乘以这个“数+1”，后面直接把5×5的结果（25）接上就行。

After the square value of the number with 5, it is equal to the previous "number" multiplied by this "this number+1", and the result of 5×5(25) is connected directly to the line.