Răspuns:
Explicație pas cu pas:
54°13'48'' + 18°58'25 = 72°71'73'' = 72°72'13'' = 73°12'13''
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149°2'16'' + 3°58'56'' = 152°60'72'' = 152°61'12'' = 153°1'12''
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64°18' - 58°3'16'' = 64°17'60'' - 58°3'16'' = 6°14'44''
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21° - 4°3' = 20°60' - 4°3' = 16°57'
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55° : 2 = 27,5° = 27°30'
sau 55° : 2 = 54°60' : 2 = 27°30'
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13°48'52'' * 2 = 26°96'104'' = 26°97'44'' = 27°37'44''
