In question ,it is not given that by how much the numerator is less ...so i assume it to be 1
Let the numeration be x
And denominator be y
∴ original fraction will be xy
Now, According to question:
⇒x+1y−1=12
⇒2x+2=y−1
⇒x=y−32 ............(A)
According to condition:
⇒x+(2x−1)y+(3y+2)=16
⇒3x−14y+2=16
⇒18x−6=4y+2
⇒18x=4y+8 ............. (B)
Put x=y−32 from Eq. (A) in Eq. (B), we get
⇒18×y−32=4y+8
⇒9y−27=4y+8
⇒5y=35
⇒y=7
Put y=7 in Eq. (B), we get
⇒18x=4×7+8
⇒x=2
Hence, the original fraction is xy=27