Question 923806
8(t+ u) = 10t + u
u = {{{(2/7)t}}}
.......
10t + u - 45 = 10u + t
9t -9u = 45
(63/7)t-9(2/7)t = 45
(45/7)t = 45
t = (7/45)45
t = 7   and u = 2 {{{(2/7)7}}}
Number is {{{ highlight_green(72)}}} 
and...checking
72 - 45 = 27