下面各题，能简便计算的用简便方法计算．4500-268×1532.4-6.79+7.6-3.21813÷7+17×5131÷[(12+57)×1415]．

Question

下面各题，能简便计算的用简便方法计算．
4500-268×15
32.4-6.79+7.6-3.21
(8)/(13)÷7+(1)/(7)×(5)/(13)
1÷[((1)/(2)+(5)/(7))×(14)/(15)]．

Answer 1

（1）4500-268×15
=4500-4020
=480

（2）32.4-6.79+7.6-3.21
=（32.4+7.6）-（6.79+3.21）
=40-10
=30

（3）(8)/(13)÷7+(1)/(7)×(5)/(13)
=(8)/(13)×(1)/(7)+(1)/(7)×(5)/(13)
=（(8)/(13)+(5)/(13)）×(1)/(7)
=1×(1)/(7)
=(1)/(7)

（4）1÷[((1)/(2)+(5)/(7))×(14)/(15)]
=1÷[(17)/(14)×(14)/(15)]
=1÷(17)/(15)
=(15)/(17)