After moving the decimal point of a decimal one place to the left, the number obtained is 13.86 less than the original number. What is the original number?

After moving the decimal point of a decimal one place to the left, the number obtained is 13.86 less than the original number. What is the original number?

After moving the decimal point of a decimal one place to the left, the number obtained is 1 / 10 of the original number, which is 1-1 / 10 less than the original number = 9 / 10
So the original number is 13.89 / (9 / 10) = 15.4