The sum of the digits of a positive three digit number Is 19. The tens digits is four less than twice the hundreds digit. The number is decreased by 99 when the digits are reversed. Find the number

Answer 1

call it
A*100 + B*10 + C
then we know

A + B + C = 19

B + 4 = 2 A

C*100 + B*10 + A + 99 = A*100 + B*10 + C

now plug and chug

Answer 2

685