If the radius of earth decrease by 10% , the mass remaining unchanged , then the acceleration due to gravity

R2=R1-10%R1=R1-10100R1=R1-0.1R1=0.9R1 g=GMR2⇒gα1R2 ⇒g2g1=R1R22 ⇒g2g1-1100=R1R22-1×100 ⇒g%=R10.9R12-1×100=10.81-1×100==1-0.810.81×100=0.190.81×100=23.45%