39 + ___ = 69 - 30, 8 tens 7 ones - 3 tens= ___ - 5 tens 7 ones, ___ + 5 tens = 7 tens - 2 tens, ___ + 5 tens 6 ones = 8 tens 6 ones - 3 tens, 48 ones - 2 tens = ___ tens ___ ones - 2 tens 8 ones,

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