= (140 + 7/30) - (138 + 5/12)
= 140 + 7/30 - 138 - 5/12
= 140 - 138 + 7/30 - 5/12
= 2 + (28/120) - (60/120)
= 2 - 32/120
= 2 - 8/30
= 2 - 4/15
= 30/15 - 4/15
= 26/15
Therefore, (140 7/30 - 138 5/12) = 18 1/16 is incorrect. The correct answer is 26/15.
= (140 + 7/30) - (138 + 5/12)
= 140 + 7/30 - 138 - 5/12
= 140 - 138 + 7/30 - 5/12
= 2 + (28/120) - (60/120)
= 2 - 32/120
= 2 - 8/30
= 2 - 4/15
= 30/15 - 4/15
= 26/15
Therefore, (140 7/30 - 138 5/12) = 18 1/16 is incorrect. The correct answer is 26/15.