10B+A=2*( 10A+B)
A/B=8/ 19, and there is no such one-bit integer.
Suppose this number is three digits, the first two digits are AB and the last digit is C.
100C+AB=2*( 10AB+C)
AB/C=98/ 19, which does not exist.
Suppose it's a four-digit ABCD
1000D+ABC = 2 *( 10 ABC+D)
ABC/D=998/ 19 does not exist.
......
It can be seen that when the n power of 10 -2 is a multiple of 19, it is the correct answer.
When N= 17,1017-2 = 99999999999998 is a multiple of 19, that is, the original number is 18 digits, ABCDEFGHIJKLMNOPQR.
ABCDEFGHIJKLMNOPQ/R = 5263 157894736842
At this time, R= 1, and the ratio is 16, and then put r before105263157894736842.
The admission rules for liberal arts in Changchun University of Technology in 2022 have been announced. The following is the