(a/b)²/（2a²/5b²）*a/5b

(a/b)²/（2a²/5b²）*a/5b
(a/b)²/（2a²/5b²）*a/5b

(a/b)²/（2a²/5b²）*a/5b
(a/b)²/（2a²/5b²）*a/5b
=(a²/b²)*(5b²)/(2a²)*a/(5b)
=(5/2)*a/(5b)
=a/(2b)

(a/b)²/（2a²/5b²）*a/5b
=a²/b²*（5b²/2a²*a/5b
=a/2b

原式=(a/b^2)*(5b^2/2a^2)*a/5b.
=(a^2*5b^2)/(2a^2b^2*5b).
=(a^2/a^2)*(5b^2/(2*5b^3).
=1*(1/2b).
=1/2b