If the decimal part of a number is enlarged by 4 times, it becomes 2.6. If the decimal part of this number is enlarged by 7 times, it becomes 3.8, then what is the number.
一个数的小数部分扩大4倍就变成2.6．如果这个数的小数部分扩大7倍就变成3.8，那么这个数是多少．
<result>1.4</result>