Eleven out of twelve divided by the unknown multiplied by two fifths equals three eighths OK, extra
1
(11/12)/a*2/5=3/8
(11/12)/a=3/8*5/2
11/12=15a/16
15a=11/12*16
a=44/3*1/15
a=44/45
2
(11/12)/(a*2/5)=3/8
11/12=3/8*2a/5
11/12=3a/20
a=11/12*20/3
a=55/9