Hello,
Let's assume
a the lowest number
b the tallest.
HCF(a,b)=56
LCM(a,b)=1568
ab=HCFLCM=(2^57^2)(2^37)=2^87^3
a=56x
b=56y
ab=56²xy==>xy=2^27
The numbers possible are (561,5628),(562,5614),(564,567)
(561,5628)=(56,1568) is excluded.
(562,5614)=(112,784) has like HCF=112 and not 56.
The answer is (564,56*7)=(224,392) which HCF is 56 and LCM=1568.