∠COA=1/3 ∠AOB=100°42‘24’‘x1/3=99°102'24''x1/3=33°34’8‘’
∠AOE=1/2 ∠AOB=100°42‘24’‘x1/2=50°21'12''
∠COE=∠AOE-∠COA=50°21'12''-33°34’8‘’=49°81‘12’‘-33°34’8‘’=16°47’4‘’
∠COA=1/3 ∠AOB=100°42‘24’‘x1/3=99°102'24''x1/3=33°34’8‘’
∠AOE=1/2 ∠AOB=100°42‘24’‘x1/2=50°21'12''
∠COE=∠AOE-∠COA=50°21'12''-33°34’8‘’=49°81‘12’‘-33°34’8‘’=16°47’4‘’