Caculate the mass lost during heating

mass of crucible and lid 21.32g
mass of KClO3 1.25g
mass of cruible/lid and residue 22.11g (1st heating)
mass of crucible/lid and residue 22.09g (2nd heating)

appreciate the help

(22.09 g - 21.32 g) = 0.77 g is the mass of residue remaining

1.25 g - 0.77 g = 0.48 g is the mass lost