We have formula for the relation between apparent dip and true dip: -

let angle of apparent dip be x

angle of true dip be y

angle eith plane is z

tan(x) = tan(y)/cos(z)

is the relation ..

now acc to the question

x= 45 and z=30

tanx=1 and tanz=1/rt(3)

so tany=1/rt(3) so y= 30 degree

hope it is correct and helpful