Answer:

36%

Step-by-step explanation:

Square A's side = x

Area = a² = x²

Square B's side = 4x/5

Area = a² = (4x/5)²

= 16x²/25

Reduced percentage,

x² = 100%

16x²/25 = ? %

= [(16x²/25) × (100)] ÷ x²

= (16x² × 100) ÷ (25 × x²)

= 64%

The reduce percentage is (100-64)  36%