Question

直接寫出得數(shù) 1 8 - 1 9 =	1 12 + 1 6 =	1 3 + 1 4 =
3 7 - 1 7 =	1- 1 2 - 1 3 =	5 14 - 1 7 =
1 3 + 1 6 + 1 4 =

Answer 1

分析：利用同分母分?jǐn)?shù)加減法法則：分母不變，只把分子相加減；異分母分?jǐn)?shù)的加減法法則：先通分，按照同分母分?jǐn)?shù)的加減法計(jì)算法則計(jì)算即可．

解答：

解： 1 8 - 1 9 = 1 72	1 12 + 1 6 = 1 4	1 3 + 1 4 = 7 12
3 7 - 1 7 = 2 7	1- 1 2 - 1 3 = 1 6	5 14 - 1 7 = 3 14
1 3 + 1 6 + 1 4 = 3 4 ．

點(diǎn)評(píng)：此題考查分?jǐn)?shù)加減法計(jì)算方法，注意計(jì)算結(jié)果的化簡(jiǎn)．